keyword abstract
keyword and
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keyword as
keyword asm
keyword begin
keyword case
keyword class
keyword const
keyword constructor
keyword contains
keyword destructor
keyword dispinterface
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keyword do
keyword downto
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keyword exports
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keyword in
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keyword inherited
keyword initialization
keyword inline
keyword interface
keyword is
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keyword packed
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keyword protected
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type AnsiChar
type AnsiString
type BOOL
type Boolean
type Byte
type Cardinal
type Char
type Comp
type Currency
type Double
type DWORD
type Extended
type HBITMAP
type HCURSOR
type HMODULE
type HPALETTE
type HRESULT
type HWND
type IDispatch
type IInterface
type Integer
type Int64
type IUnknown
type LongBool
type Longint
type LongWord
type OleVariant
type PAnsiChar
type PByte
type PChar
type PDateTime
type PFileInfo
type PGUID
type Pointer
type PPTypeInfo
type PShortString
type PTypeInfo
type PVarData
type PWChar
type PWideChar
type PWord
type Real
type Real48
type ShortInt
type ShortString
type SmallInt
type Single
type string
type TBasicAction
type TBasicActionClass
type TBooleanToStringRule |(bsrAsIs, bsrLower, bsrUpper)
type TClass
type TCollection
type TColor
type TComponent
type TControl
type TDateTime
type TEnumActionProc
type TFileStream
type TFont
type TFontCharset
type TFormatSettings
type TGetStrProc |procedure(const S: string) of object
type TGUID
type THandle
type THeapStatus
type THelpContext
type TIdentMapEntry
type TIdentToInt |function(const Ident: string; var Int: Longint): Boolean
type TIntToIdent |function(Int: Longint; var Ident: string): Boolean
type TMainMenu
type TMbcsByteType |(mbSingleByte, mbLeadByte, mbTrailByte)
type TMemoryManager
type TMenuItem
type TMouse
type TNotifyEvent
type TObject
type TPersistent
type TPersistentClass
type TPoint
type TPopupAlignment
type TPopupMenu
type TPrinter
type TProcedure
type TRect
type TRoundToRange
type TScreen
type TSearchRec
type TShiftState
type TShortCut
type TSimpleRoundToRange
type TSmallPoint
type TSQLTimeStamp
type TStream
type TStreamOriginalFormat |(sofUnknown, sofBinary, sofText)
type TStrings
type TStringList
type TStringSearchOption |(soDown, soMatchCase, soWholeWord)
type TStringSearchOptions |set of TStringSearchOption
type TSysCharSet
type TSysLocale
type TSystemTime
type TTerminateProc
type TTextLineBreakStyle |(tlbsLF, tlbsCRLF)
type TTextRec
type TThreadFunc
type TTimeStamp
type TTypeInfo
type TTypeKind |(tkUnknown, tkInteger, tkChar, tkEnumeration, tkFloat, tkString, tkSet, tkClass, tkMethod, tkWChar, tkLString, tkWString, tkVariant, tkArray, tkRecord, tkInterface, tkDynArray)
type TValueSign |-1..1
type TVarData
type TVarDispProc
type TVariantRelationship |(vrEqual, vrLessThan, vrGreaterThan, vrNotEqual)
type TVarType
type TWndMethod |procedure(var Message: TMessage) of object
type TWinControl
type UINT
type UnicodeString
type UTF8String
type Variant
type WideChar
type WideString
type Word
type WordBool

procedure Abort |Raises a silent exception.
function Abs(X) |Returns the absolute value of a number.
function AcquireExceptionObject: Pointer |Retains access to exception object.
procedure ActivateClassGroup(AClass: TPersistentClass): TPersistentClass |Activates a group of classes that derive from TPersistent.

procedure AddExitProc(Proc: TProcedure) |Adds a procedure to the exit list.
function Addr(X): Pointer |Returns the address of a variable or routine.
procedure AddTerminateProc(TermProc: TTerminateProc) |Adds a terminate procedure to the system list of termination procedures.
function AdjustLineBreaks(const S: string; Style: TTextLineBreakStyle = tlbsCRLF): string |Adjusts line break characters to reflect Windows or Linux style.

function AllocateHwnd(Method: TWndMethod): HWND |Creates a window that implements a specified window procedure.
function AllocFileInfo(SearchRec: TSearchRec): PFileInfo |Creates new file info object.
function AllocMem(Size: Cardinal): Pointer |Allocates a memory block and initializes each byte to zero.
var AllocMemCount: Integer |Represents the total number of allocated memory blocks in a Delphi application.
var AllocMemSize: Integer |Represents the total size of allocated memory blocks.

function AnsiCompareFileName(const S1, S2: string): Integer |Compares file names based on the current locale.
function AnsiCompareStr(const S1, S2: string): Integer |Compares strings based on the current locale with case sensitivity.
function AnsiCompareText(const S1, S2: string): Integer |Compares strings based on the current locale without case sensitivity.
function AnsiContainsStr(const AText, ASubText: string): Boolean |Indicates whether one string is a (case-sensitive) substring of another.
function AnsiContainsText(const AText, ASubText: string): Boolean |Indicates whether one string is a (case-insensitive) substring of another.
function AnsiDequotedStr(const S: string; AQuote: Char): string |Converts a quoted string into an unquoted string
function AnsiEndsStr(const ASubText, AText: string): Boolean |Indicates whether one string is a (case-sensitive) suffix of another.
function AnsiEndsText(const ASubText, AText: string): Boolean |Indicates whether one string is a (case-insensitive) suffix of another.
function AnsiExtractQuotedStr(var Src: PChar; Quote: Char): string |Converts a quoted string into an unquoted string.
function AnsiIndexStr(const AText: string; const AValues: array of string): Integer |Provides the index of a specified string in an array of strings.
function AnsiIndexText(const AText: string; const AValues: array of string): Integer |Provides the index of a specified string in an array of strings.
function AnsiLastChar(const S: string): PChar |Returns a pointer to the last character in a string.
function AnsiLeftStr(const AText: AnsiString; const ACount: Integer): AnsiString |Returns the substring of a specified length that appears at the start of a string.
function AnsiLowerCase(const S: string): string |Returns a string that is a copy of the given string converted to lower case.
function AnsiLowerCaseFileName(const S: string): string |Converts a file name to lower case.
function AnsiMatchStr(const AText: string; const AValues: array of string): Integer |Indicates whether an array of strings contains an exact match to a specified string.
function AnsiMatchText(const AText: string; const AValues: array of string): Integer |Indicates whether an array of strings contains a case-insensitive match to a specified string.
function AnsiMidStr(const AText: AnsiString; const AStart, ACount: Integer): AnsiString |Returns the substring of a specified length that appears at a specified position in a string.
function AnsiPos(const Substr, S: string): Integer |Locates the position of a substring.
function AnsiQuotedStr(const S: string; Quote: Char): string |Returns the quoted version of a string.
function AnsiReplaceStr(const AText, AFromText, AToText: string): string |Replaces all occurrences of a substring with another string.
function AnsiReplaceText(const AText, AFromText, AToText: string): string |Replaces all case-insensitive matches of a substring with another string.
variable AnsiResemblesProc: TCompareTextProc |Controls the algorithm used by AnsiResemblesText to determine when two strings are similar.
function AnsiResemblesText(const AText, AOther: string): Boolean |Indicates whether two strings are similar.
function AnsiReverseString(const AText: AnsiString): AnsiString |Returns reversed string.
function AnsiRightStr(const AText: AnsiString; const ACount: Integer): AnsiString |Returns the substring of a specified length that appears at the end of a string.
function AnsiSameCaption(const Text1, Text2: string): Boolean |Indicates whether two strings are the same based on the current locale, ignoring case information and accelerator characters.
function AnsiSameStr(const S1, S2: string): Boolean |Compares strings based on the current locale with case sensitivity.
function AnsiSameText(const S1, S2: string): Boolean |Compares strings based on the current locale without case sensitivity.
function AnsiStartsStr(const ASubText, AText: string): Boolean |Indicates whether one string is a (case-sensitive) prefix of another.
function AnsiStartsText(const ASubText, AText: string): Boolean |Indicates whether one string is a (case-insensitive) prefix of another.

function AnsiStrComp(S1, S2: PChar): Integer |Compares null-terminated character strings.
function AnsiStrIComp(S1, S2: PChar): Integer |Compares null terminated character strings case insensitively.
function AnsiStrLastChar(P: PChar): PChar |Returns a pointer to the last character in a null-terminated string.
function AnsiStrLComp(S1, S2: PChar; MaxLen: Cardinal): Integer |Compares the first MaxLen bytes of two null-terminated strings, case-sensitively.
function AnsiStrLIComp(S1, S2: PChar; MaxLen: Cardinal): Integer |Compares two strings, case-insensitively, up to the first MaxLen bytes.
function AnsiStrLower(Str: PChar): PChar |Converts all characters in a null-terminated string to lower case.
function AnsiStrPos(Str, SubStr: PChar): PChar |Returns a pointer to the first occurrence of a substring.
function AnsiStrRScan(Str: PChar; Chr: Char): PChar |Returns a pointer to the last occurrence of a specified character in a specified string.
function AnsiStrScan(Str: PChar; Chr: Char): PChar |Returns a pointer to first occurrence of a character in a string.
function AnsiStrUpper(Str: PChar): PChar |Converts all characters in a null-terminated string to upper case.

function AnsiToUtf8(const S: string): UTF8String |Converts a string encoded in Ansi to UTF-8.
function AnsiUpperCase(const S: string): string |Converts a string to upper case.
function AnsiUpperCaseFileName(const S: string): string |Converts a file name to upper case.

procedure Append(Text: string) |Prepares an existing file for adding text to the end.
procedure AppendStr(var Dest: string; const S: string); deprecated |Appends a dynamically allocated string to an existing string.

function ArcCos(const X: Extended): Extended |Calculates the inverse cosine of a given number.
function ArcCosh(const X: Extended): Extended |Calculates the inverse hyperbolic cosine of a given number.
function ArcCot(const X: Extended): Extended |Calculates the inverse cotangent of a given number.
function ArcCotH(const X: Extended): Extended |Calculates the inverse hyperbolic cotangent of a given number.
function ArcCsc(const X: Extended): Extended |Calculates the inverse cosecant of a given number.
function ArcCscH(const X: Extended): Extended |Calculates the inverse hyperbolic cosecant of a given number.
function ArcSec(const X: Extended): Extended |Calculates the inverse secant of a given number.
function ArcSecH(const X: Extended): Extended |Calculates the inverse hyperbolic secant of a given number.
function ArcSin(const X: Extended): Extended |Calculates the inverse sine of a given number.
function ArcSinh(const X: Extended): Extended |Calculates the inverse hyperbolic sine of a given number.
function ArcTan(const X: Extended): Extended |Calculates the arctangent of a given number.
function ArcTan2(const Y, X: Extended): Extended |Calculates the arctangent angle and quadrant of a given number.
function ArcTanh(const X: Extended): Extended |Calculates the inverse hyperbolic tangent of a given number.

function Assigned(const P): Boolean |Determines if the pointer or procedure referenced is not nil (assigned)
procedure AssignFile(var F; FileName: string) |Associates the name of an external file with a file variable.
procedure AssignPrn(var F: Text) |Assigns a text file variable to the printer.
procedure AssignStr(var P: PString; const S: string); deprecated |Assigns a new dynamically allocated string to a specified pointer.
procedure Assert(expr: Boolean [; const msg: string]) |Use Assert as a debugging tool to test that certain conditions are always True (as assumed).
var AssertErrorProc: Pointer |Points to the assertion error-handler.
procedure Beep |Generates a conventional message beep.

function BeginThread(SecurityAttributes: Pointer; StackSize: LongWord; ThreadFunc: TThreadFunc; Parameter: Pointer; CreationFlags: LongWord; var ThreadId: LongWord): Integer |Spawns a separate thread of execution.
procedure BinToHex(Buffer, Text: PChar; BufSize: Integer) |Converts a binary value to its hexadecimal representation.
procedure BlockRead(var F: File; var Buf; Count: Integer [; var AmtTransferred: Integer]) |Reads one or more records from an open file into a variable.
procedure BlockWrite(var f: File; var Buf; Count: Integer [; var AmtTransferred: Integer]) |Writes one or more records from a variable to an open file.

var BooleanToStringRule: TBooleanToStringRule |Specifies rule fixing up Boolean values converted to strings.
function BoolToStr(B: Boolean; UseBoolStrs: Boolean = False): string |Returns a string from a boolean value.
function Bounds(ALeft, ATop, AWidth, AHeight: Integer): TRect |Returns the TRect type variable from a rectangle.
procedure Break |Immediately exits the iteration in which it appears.
function ButtonStateToShiftState(ButtonState: Qt.ButtonState): TShiftState |Converts Qt button state value.

function ByteToCharIndex(const S: string; Index: Integer): Integer |Returns the position of the character that contains a specified byte in a string.
function ByteToCharLen(const S: string; MaxLen: Integer): Integer |Returns the number of characters fully contained in the first MaxLen bytes of a string.
function ByteType(const S: string; Index: Integer): TMbcsByteType |Indicates whether a byte in a string is a single byte character, the first byte of a double byte character, or the second byte of a double byte character.

function CallTerminateProcs: Boolean |Calls all of the functions in the termination procedure list.
function Ceil(const X: Extended): Integer |Returns the largest near integer number.
function CenterPoint(const Rect: TRect): TPoint |Returns the point in the center of a rectangle.
function ChangeFileExt(const FileName, Extension: string): string |Changes the extension part of a string containing full path and file name.

function CharLength(const S: String; Index: Integer): Integer |Returns number of bytes used by a character.
function CharsetToIdent(Charset: Longint; var Ident: string): Boolean |Obtains the name of a character set.
function CharToByteIndex(const S: string; Index: Integer): Integer |Returns the 1-based index of the first byte of a specified character in a string.
function CharToByteLen(const S: string; MaxLen: Integer): Integer |Returns the length, in bytes, of the first MaxLen characters of a string.
procedure ChDir(const S: string) |Changes the current directory.

procedure CheckRange(AMin, AMax: Integer) |Verifies that integer pair is valid range.
procedure CheckSqlTimeStamp(const ASQLTimeStamp : TSQLTimeStamp) |Checks whether a TSQLTimeStamp value represents a valid date and time.
function CheckSynchronize(Timeout: Integer = 0): Boolean |Allows background threads to synchronize their execution with the main thread.
procedure CheckToolMenuDropdown(ToolButton: TToolButton) |Displays a tool button’s dropdown menu.

function Chr(X: Byte): Char |Returns the character for a specified ASCII value.
function Clipboard: TClipboard |Returns an instance of TClipboard.
procedure Close(var F) |Terminates the association between a file variable and an external file.
procedure CloseFile(var F) |Terminates the association between file variable and an external disk file.
function CollectionsEqual(C1, C2: TCollection; Owner1, Owner2: TComponent): Boolean |Compares the contents of two collections.

function ColorToIdent(Color: Longint; var Ident: string): Boolean |Provides the symbolic name of a TColor value.
function ColorToRGB(Color: TColor): Longint |Converts a TColor value into an RGB representation of the color.
function ColorToString(Color: TColor): string |Returns a string that represents the name of a TColor value.

function CompareStr(const S1, S2: string): Integer |Compares two strings.
function CompareDate(const A, B: TDateTime): TValueRelationship |Compares two TDateTime values (returns "less", "equal" or "greater"). Ignores the Time part if both values "fall" on the same day.
function CompareDateTime(const A, B: TDateTime): TValueRelationship |Compares two TDateTime values (returns "less", "equal" or "greater").
function CompareMem(P1, P2: Pointer; Length: Integer): Boolean |Performs a binary comparison of two memory images.
function CompareText(const S1, S2: string): Integer |Compares two strings without case sensitivity.
function CompareTime(const A, B: TDateTime): TValueRelationship |Compares two TDateTime values (returns "less", "equal" or "greater"). Ignores the Date part if both values occur at the same time.
function CompareValue(const A, B: Extended; Epsilon: Extended = 0): TValueRelationship |Returns the relationship between two numeric values.
function CompToCurrency(Value: Comp): Currency |Converts a Comp value to a Currency value.
function CompToDouble(Value: Comp): Double |Converts a Comp value to a Double value.

function Concat(s1 [, s2,..., sn]: string): string |Concatenates two or more strings into a single string.
procedure Continue |Passes control to the next iteration of the enclosing iteration statement in which it appears.
function Copy(S; Index, Count: Integer): string |Returns a substring of a string or a segment of a dynamic array.
function CopyPalette(Category: HPALETTE): HPALETTE |Creates a new palette object that matches an existing palette.

function Cos(const X: Extended): Extended |Calculates the cosine of an angle.
function Cosecant(const X: Extended): Extended |Returns the cosecant of an angle.
function Cosh(const X: Extended): Extended |Calculates the hyperbolic cosine of an angle.
function Cot(const X: Extended): Extended |Calculates the cotangent of an angle.
function Cotan(const X: Extended): Extended |Calculates the cotangent of an angle.
function CotH(const X: Extended): Extended |Calculates the hyperbolic cotangent of an angle.

function CountGenerations(Ancestor, Descendant: TClass): Integer |Returns the number of intermediate classes between a derived class and its ancestor.

function CreateAction(AOwner: TComponent; ActionClass: TBasicActionClass): TBasicAction |Creates an action of a specified type.
function CreateDir(const Dir: string): Boolean |Creates a new directory.
function CreateGrayMappedBmp(Handle: HBITMAP): HBITMAP |Remaps the standard gray colors in a bitmap with the system grays.
function CreateGrayMappedRes(Instance: THandle; ResName: PChar): HBITMAP |Remaps the standard gray colors in a bitmap resource with the system grays.
function CreateGUID(out Guid: TGUID): HResult |Creates a globally unique identifier.
function CreateMappedBmp(Handle: HBITMAP; const OldColors, NewColors: array of TColor): HBITMAP |Changes the color table in a bitmap.
function CreateMappedRes(Instance: THandle; ResName: PChar; const OldColors, NewColors: array of TColor): HBITMAP |Changes the color table in a bitmap resource.
function CreateMessageDialog(const Msg: string; DlgType: TMsgDlgType; Buttons: TMsgDlgButtons): TForm |Returns a specified message dialog, does not display the dialog form.

function Csc(const X: Extended): Extended |Returns the cosecant of an angle.
function CscH(const X: Extended): Extended |Returns the hyperbolic cosecant of an angle.

procedure CurrencyToComp(Value: Currency; var Result: Comp) |Converts a Currency value to a Comp value.
function CurrentYear: Word |Returns the current year.
function CurrToStr(Value: Currency[; const FormatSettings: TFormatSettings]): string |Converts a currency value to a string.
function CurrToStrF(Value: Currency; Format: TFloatFormat; Digits: Integer): string |Converts a Currency value to a string, using a specified format.
function CursorToIdent(Cursor: Longint; var Ident: string): Boolean |Returns the name of the predefined constant that corresponds to a cursor.
function CursorToString(Cursor: TCursor): string |Returns the string representation of a cursor.

procedure DatabaseError(const Message: string; Component: TComponent = nil) |Creates and raises an EDatabaseError exception.
procedure DatabaseErrorFmt(const Message: string; const Args: array of const; Component: TComponent = nil) |Creates and raises an EDatabaseError exception with a formatted error message.

function Date: TDateTime |Returns the current system date.
const DateDelta |Specifies the difference between TDateTime and TTimeStamp values.
function DateOf(const AValue: TDateTime): TDateTime |Returns only the Date portion of the TDateTime value, by setting Time part to 0.
function DateTimeToFileDate(DateTime: TDateTime): Integer |Converts a TDateTime value to a system timestamp value.
function DateTimeToSQLTimeStamp(const DateTime: TDateTime): TSQLTimeStamp |Converts a TDateTime value to a TSQLTimeStamp value.
function DateTimeToStr(DateTime: TDateTime[; const FormatSettings: TFormatSettings]): string |Converts a TDateTime value to a string (date and time).
procedure DateTimeToString(var Result: string; const Format: string; DateTime: TDateTime[; const FormatSettings: TFormatSettings]) |Converts a TDateTime value to a string using a specified Format.
procedure DateTimeToSystemTime(DateTime: TDateTime; var SystemTime: TSystemTime) |Converts a TDateTime value into the Win32 API's system time type.
function DateTimeToTimeStamp(DateTime: TDateTime): TTimeStamp |Converts a TDateTime value into the corresponding TTimeStamp value.
function DateToStr(Date: TDateTime): string |Converts a TDateTime value to a string (date part only).
function DayOf(const AValue: TDateTime): Word |Returns the day of the month represented by a TDateTime value.
function DayOfTheMonth(const AValue: TDateTime): Word |Returns the day of the month represented by a TDateTime value.
function DayOfTheWeek(const AValue: TDateTime): Word |Returns the day of the week represented by a TDateTime value.
function DayOfTheYear(const AValue: TDateTime): Word |Returns the number of days between a specified TDateTime value and December 31 of the previous year.
function DayOfWeek(Date: TDateTime): Word |Returns the day of the week for a given date.
function DaysBetween(const ANow, AThen: TDateTime): Integer |Gives the number of whole days between two specified dates.
function DaysInAMonth(const AYear, AMonth: Word): Word |Returns the number of days in a specified month of a specified year.
function DaysInAYear(const AYear: Word): Word |Returns the number of days in a specified year.
function DaysInMonth(const AValue: TDateTime): Word |Returns the number of days in the month of a specified TDateTime value.
function DaysInYear(const AValue: TDateTime): Word |Returns the number of days in the year of a specified TDateTime value.
function DaySpan(const ANow, AThen: TDateTime): Double |Gives the number of days (including fractional days) between two specified dates.

var DDBsOnly: Boolean |Determines whether bitmap handles are created as device-dependent bitmaps (DDB).
procedure DeallocateHwnd(Wnd: HWND) |Frees a window that was created using AllocateHWnd.
procedure Dec(var X [; N: Longint]) |Decrements a variable by 1 or N.

procedure DecodeDate(Date: TDateTime; var Year, Month, Day: Word) |Separates Year, Month, and Day values from a TDateTime value.
procedure DecodeDateDay(const AValue: TDateTime; out AYear, ADayOfYear: Word) |Returns the year and day of the year for a specified TDateTime.
function DecodeDateFully(const DateTime: TDateTime; var Year, Month, Day, DOW: Word): Boolean |Returns Year, Month, and Day, and Day-of-Week values for a TDateTime value.
procedure DecodeDateMonthWeek(const AValue: TDateTime; out AYear, AMonth, AWeekOfMonth, ADayOfWeek: Word) |Returns the year, month, week of the month, and day of the week for a specified TDateTime.
procedure DecodeDateTime(const AValue: TDateTime; out AYear, AMonth, ADay, AHour, AMinute, ASecond, AMilliSecond: Word) |Returns Year, Month, Day, Hour, Minute, Second, and Millisecond values for a TDateTime.
procedure DecodeDateWeek(const AValue: TDateTime; out AYear, AWeekOfYear, ADayOfWeek: Word) |Returns the year, week of the year, and day of the week for a specified TDateTime value.
procedure DecodeDayOfWeekInMonth(const AValue: TDateTime; out AYear, AMonth, ANthDayOfWeek, ADayOfWeek: Word) |For a given TDateTime value, returns the year, month, day of the week, and the count of that day of the week in the month.

function DecodeSoundExInt(AValue: Integer): string |Converts an integer representation of a SoundEx encoding into the corresponding phonetic string.
function DecodeSoundExWord(AValue: Word): string |Converts a Word representation of a SoundEx encoding into the corresponding phonetic string.
procedure DecodeTime(Time: TDateTime; var Hour, Min, Sec, MSec: Word) |Separates Hour, Minute, Second, and MilliSecond values from a TDateTime value.

var Default8087CW: Word |Specifies the Default 8087 control word.
var DefaultTextLineBreakStyle: TTextLineBreakStyle |Specifies the characters that are used by default to separate lines in text.
function DegToCycle(const Degrees: Extended): Extended |Returns the value of a degree measurement expressed in cycles.
function DegToGrad(const Degrees: Extended): Extended |Returns the value of a degree measurement expressed in grads.
function DegToRad(const Degrees: Extended): Extended |Returns the value of a degree measurement expressed in radians.
procedure Delete(var S: string; Index, Count:Integer) |Removes a substring from a string.
function DeleteFile(const FileName: string): Boolean |Deletes a specified file.
procedure DestroyMetaPict(MetaPict: HGlobal) |Frees a metafile resource given its handle.
function DirectoryExists(const Directory: string): Boolean |Determines whether a specified directory exists.
procedure Dispose(var P: Pointer) |Releases memory allocated for a dynamic variable.
procedure DisposeStr(P: PString); deprecated |Disposes of a string pointer that was allocated using NewStr.
procedure DivMod(Dividend: Integer; Divisor: Word; var Result, Remainder: Word) |Returns the integer and the remainder of an integer division, in one operation.
function DirectoryExists(const Directory: string): Boolean |Returns True if a specified directory exists.
function DiskFree(Drive: Byte): Int64 |Returns the amount of free space in bytes on a specified drive.
function DiskSize(Drive: Byte): Int64 |Returns the size in bytes of a specified drive.
var DLLProc: Pointer |Points to a procedure invoked by a DLL entry point.
function DoubleToComp(Value: Double; var Result: Comp) |Converts a double value to a Comp.

function DrawButtonFace(Canvas: TCanvas; const Client: TRect; BevelWidth: Integer; Style: TButtonStyle; IsRounded, IsDown, IsFocused: Boolean): TRect |Draws a push button.
function DupeString(const AText: string; ACount: Integer): string |Returns a string repeated a specified number of times.

procedure DynArrayFromVariant(var DynArray: Pointer; const V: Variant; TypeInfo: Pointer) |Creates a dynamic array from a Variant.
procedure DynArrayToVariant(var V: Variant; const DynArray: Pointer; TypeInfo: Pointer) |Creates a Variant array from a dynamic array.
var EmptyParam: OleVariant |Contains an OleVariant that represents an unused optional parameter on a dual interface.

function EncodeDate(Year, Month, Day: Word): TDateTime |Creates a TDateTime value from Year, Month, and Day values.
function EncodeDateDay(const AYear, ADayOfYear: Word): TDateTime |Returns a TDateTime that represents a specified day of the year for a specified year.
function EncodeDateMonthWeek(const AYear, AMonth, AWeekOfMonth: Word; const ADayOfWeek: Word = 1): TDateTime |Returns a TDateTime that represents a specified day of a specified week in a specified month and year.
function EncodeDateTime(const AYear, AMonth, ADay, AHour, AMinute, ASecond, AMilliSecond: Word): TDateTime |Returns a TDateTime that represents a specified year, month, day, hour, minute, second, and millisecond.
function EncodeDateWeek(const AYear, AWeekOfYear: Word; const ADayOfWeek: Word = 1): TDateTime |Returns a TDateTime that represents a specified day of a specified week in a specified year.
function EncodeDayOfWeekInMonth(const AYear, AMonth, ANthDayOfWeek, ADayOfWeek: Word): TDateTime |Returns a TDateTime that represents a specified occurrence of a day of the week within a specified month and year.
function EncodeTime(Hour, Min, Sec, MSec: Word): TDateTime |Creates a TDateTime value from Hour, Min, Sec, and MSec. values.
function EndOfADay(const AYear, AMonth, ADay: Word): TDateTime |Returns a TDateTime that represents the last millisecond of a specified day.
function EndOfAMonth(const AYear, AMonth: Word): TDateTime |Returns a TDateTime that represents the last millisecond of the last day of a specified month.
function EndOfAWeek(const AYear, AWeekOfYear: Word; const ADayOfWeek: Word = 7): TDateTime |Returns a TDateTime value that represents the last millisecond of a specified day of a specified week.
function EndOfAYear(const AYear): TDateTime |Returns a TDateTime that represents the last millisecond of a specified year.
function EndOfTheDay(const AValue: TDateTime): TDateTime |Returns a TDateTime that represents the last millisecond of the day identified by a specified TDateTime.
function EndOfTheMonth(const AValue: TDateTime): TDateTime |Returns a TDateTime that represents the last millisecond of the last day of the month identified by a specified TDateTime.
function EndOfTheWeek(const AValue: TDateTime): TDateTime |Returns a TDateTime that represents the last millisecond of the last day of the week identified by a specified TDateTime.
function EndOfTheYear(const AValue: TDateTime): TDateTime |Returns a TDateTime that represents the last millisecond of the last day of the year identified by a specified TDateTime.

function EndThread(ExitCode: Integer) |Terminates the execution of a thread.
function EnsureRange(const AValue, AMin, AMax: Integer): Integer |Returns the closest value to a specified value within a specified range.
procedure EnumRegisteredActions(Proc: TEnumActionProc; Info: Pointer) |Iterates through the list of registered actions, passing them to a user-defined callback.

function Eof([var F]): Boolean |Tests whether the file position is at the end of a file.
function Eoln([var F: Text]): Boolean |Tests whether the file pointer is at the end of a line.

function EqualRect(const R1, R2: TRect): Boolean |Indicates whether two TRect values are the same.
procedure Erase(var F) |Deletes a file.
var ErrorAddr: Pointer |Points to the RTL runtime error handler.
var ErrOutput: Text |Specifies a write-only Text file associated with the process's standard error file.

function ExceptAddr: Pointer |Returns the address at which the current exception was raised.
function ExceptionErrorMessage(ExceptObject: TObject; ExceptAddr: Pointer; Buffer: PChar; Size: Integer): Integer |Formats a standard error message.
function ExceptObject: TObject |Returns current exception object.
var ExceptProc: Pointer |Points to the lowest-level exception handler.

procedure Exclude(var S: set of T; I: T) |Removes an element to a set.
function ExcludeTrailingBackslash(const S: string): string |Removes '\' from the end of a string if it is there.
function ExcludeTrailingPathDelimiter(const S: string): string |Returns a path name without a trailing delimiter.

procedure Exit
var ExitCode: Integer |Contains the application's exit code.

function Exp(X: Real): Real |Returns the base of natural logarithms (e) raised to a power.
function ExpandDirectoryName(Directory: string): string |Expands directory name.
function ExpandFileName(const FileName: string): string |Retrieves the full path and filename of a specified (relative) file.
function ExpandFileNameCase(const FileName: string; out MatchFound: TFilenameCaseMatch): string |Returns the full path name for a relative file name on a case-sensitive file system.
function ExpandUNCFileName(const FileName: string): string |Retrieves the full path and filename of a specified (relative) file using Universal Naming Convention for network files.
function ExtractFileDir(const FileName: string): string |Returns only only directory or drive information parts of a string containing full path and file name.
function ExtractFileDrive(const FileName: string): string |Returns only drive part of a string containing full path and file name.
function ExtractFileExt(const FileName: string): string |Returns the extension part of a string containing full path and file name.
function ExtractFileName(const FileName: string): string |Returns only file name and extension parts of a string containing full path and file name.
function ExtractFilePath(const FileName: string): string |Returns the drive and directory parts of a string containing full path and file name.
function ExtractRelativePath(const BaseName, DestName: string): string |Returns a relative path name, relative to a specific base directory.
function ExtractShortPathName(const FileName: string): string |Returns 8.3 format for a given full path and file name.
function ExtractStrings(Separators, WhiteSpace: TSysCharSet; Content: PChar; Strings: TStrings): Integer |Fills a string list with substrings parsed from a delimited list.

var FalseBoolStrs: array of String |Lists strings that can represent the boolean value False.
var FileAccessRights: Integer |Points to the command-line arguments specified when the application is invoked.
function FileAge(const FileName: string): Integer |Returns the OS time stamp of a file.
procedure FileClose(Handle: Integer) |Closes a specified file.
function FileCreate(const FileName: string[; Rights: Integer]): Integer |Creates a new file.
function FileDateToDateTime(FileDate: Integer): TDateTime |Converts the system time stamp of a file to a TDateTime value
function FileExists(const FileName: string): Boolean |Checks whether a specified file exists.
var FileIconProviderClass: TFileIconProviderClass |Specifies class used to instantiate file icon providers.
function FileGetAttr(const FileName: string): Integer |Retrieves the attributes of a specified file.
function FileGetDate(Handle: Integer): Integer |Returns an OS timestamp for a specified file.
function FileIsReadOnly(const FileName: string): Boolean |Reports whether a file is read-only.
var FileMode: Byte |Indicates the access mode on typed and untyped files opened by the Reset procedure.
function FileOpen(const FileName: string; Mode: LongWord): Integer |Opens a specified file using a specified access mode.
function FilePos(var F): Longint |Returns the current file position.
function FileRead(Handle: Integer; var Buffer; Count: Integer): Integer |Reads a specified number of bytes from a file.
function FileSearch(const Name, DirList: string): string |Searches a specified directory path for a file.
function FileSeek(Handle: Integer; const Offset: Int64; Origin: Integer): Int64 |Repositions read/write point.
function FileSetAttr(const FileName: string; Attr: Integer): Integer |Sets the attributes of a specified file.
function FileSetDate(Handle: Integer; Age: Integer): Integer |Sets the OS time stamp for a specified file.
function FileSetReadOnly(const FileName: string; ReadOnly: Boolean): Boolean |Sets the read-only status of the specified file.
function FileSize(var F): Integer |Returns the number of records in a file.
function FileWrite(Handle: Integer; const Buffer; Count: Integer): Integer |Writes the contents of a buffer to the current position in a file.
procedure FillChar(var X; Count: Integer; Value: Byte) |Fills continuous bytes with a specified value.
procedure Finalize(var V [; Count: Integer]) |Uninitializes a dynamically allocated variable.

function FindClass(const ClassName: string): TPersistentClass |Finds and returns a class that is derived from TPersistent.
function FindClassHInstance(ClassType: TClass): LongWord |Returns the instance handle for the module in which a class type is defined.
procedure FindClose(var F: TSearchRec) |Releases memory allocated by FindFirst.
function FindCmdLineSwitch(const Switch: string; Chars: TSysCharSet; IgnoreCase: Boolean): Boolean |Returns True if a specified string was passed as a command line argument.
function FindControl(Handle: HWnd): TWinControl |Returns the control whose window is identified by the specified handle or which appears at a specified position.
function FindCustomVariantType(const TypeName: string; out CustomVariantType: TCustomVariantType): Boolean |Retrieves the object that implements a custom Variant type.
function FindCustomVariantType(const AVarType: TVarType; out CustomVariantType: TCustomVariantType): Boolean |Retrieves the object that implements a custom Variant type.

function FindFirst(const Path: string; Attr: Integer; var F: TSearchRec): Integer |Searches for the first instance of a file name with a given set of attributes in a specified directory.
function FindGlobalComponent(const Name: string): TComponent |Returns a top-level container component.
function FindHInstance(Address: Pointer): LongWord |Returns the instance handle of the module that contains a specified address.

function FindNext(var F: TSearchRec): Integer |Returns the next entry matching the name and attributes specified in a previous call to FindFirst.
function FindResourceHInstance(Instance: LongWord): LongWord |Returns the instance handle of the resource module associated with a specified HInstance.
function FindVarData(const V: Variant): PVarData |Returns pointer to variant's data.
function FindVCLWindow(const Pos: TPoint): TWinControl |Returns the windowed control, if any, at the specified location.

function FloatToCurr(const Value: Extended): Currency |Converts a floating-point value to a Currency value.
function FloatToDateTime(const Value: Extended): TDateTime |Returns a TDateTime value from a floating point value.
procedure FloatToDecimal(var DecVal: TFloatRec; const Value; ValueType: TFloatValue; Precision, Decimals: Integer) |Converts a floating-point value to a decimal representation.
function FloatToStr(Value: Extended[; const FormatSettings: TFormatSettings]): string |Returns a string from a floating point value.
function FloatToStrF(Value: Extended; Format: TFloatFormat; Precision, Digits: Integer[; const FormatSettings: TFormatSettings]): string |Returns a string from a floating point value, using a specified Format, Precision, and Digits.
function FloatToText(Buffer: PChar; const Value; ValueType: TFloatValue; Format: TFloatFormat; Precision, Digits: Integer[; const FormatSettings: TFormatSettings]): Integer |Converts a floating-point value to an unterminated character string, using a specified Format, Precision and Digits.
function FloatToTextFmt(Buffer: PChar; const Value; ValueType: TFloatValue; Format: PChar[; const FormatSettings: TFormatSettings]): Integer |Converts a floating-point value to an unterminated character string, using a specified format.
function Floor(const X: Extended): Integer |Returns the smallest near integer number.
function Flush(var t: Text): Integer |Empties the buffer of a text file opened for output.
function FmtLoadStr(Ident: Integer; const Args: array of const): string |Returns formatted output using a resourced format string.
procedure FmtStr(var StrResult: string; const Format: string; const Args: array of const[; const FormatSettings: TFormatSettings]) |Assembles a formatted string using a format string and an array of arguments.

var ForceCurrentDirectory: Boolean |Indicates whether open and save dialogs should display the current directory if no initial directory is assigned.
function ForceDirectories(Dir: string): Boolean |Creates all the folders along a given path.
function ForegroundTask: Boolean |Indicates whether the current thread is running in the foreground.

function Format(const Format: string; const Args: array of const[; const FormatSettings: TFormatSettings]): string |Returns a formatted string assembled from a format string and an array of arguments.
function FormatBuf(var Buffer; BufLen: Cardinal; const Format; FmtLen: Cardinal; const Args: array of const[; const FormatSettings: TFormatSettings]): Cardinal |Formats the arguments from an array, placing the result in a buffer.
function FormatCurr(const Format: string; Value: Currency[; const FormatSettings: TFormatSettings]): string |Returns a string from a currency point value using the provided format string.
function FormatDateTime(const Format: string; DateTime: TDateTime[; const FormatSettings: TFormatSettings]): string |Formats a TDateTime value to a string.
function FormatFloat(const Format: string; Value: Extended[; const FormatSettings: TFormatSettings]): string |Returns a string from a floating point value using the provided format string.
function FormatMaskText(const EditMask: string; const Value: string): string |Returns a string formatted using an edit mask.
function Frac(X: Extended): Extended |Returns the fractional part of a number.
procedure Frame3D(Canvas: TCanvas; var Rect: TRect; TopColor, BottomColor: TColor; Width: Integer) |Draws a three dimensional frame on a canvas.

procedure FreeAndNil(var Obj) |Frees an object reference and replaces the reference with nil (Delphi) or NULL (C++).
procedure FreeAndNilProperties(AObject: TObject) |Frees any property values that are objects and sets their value to nil (Delphi) or NULL (C++).
procedure FreeMem(var P: Pointer[; Size: Integer]) |Disposes of a dynamic variable of a given size.

procedure Frexp(const X: Extended; var Mantissa: Extended; var Exponent: Integer) |Separates the Mantissa and Exponent of X.
function FutureValue(const Rate: Extended; NPeriods: Integer; const Payment, PresentValue: Extended; PaymentTime: TPaymentTime): Extended |Returns the future value of an investment.

function Get8087CW: Word |Returns the value of the 8087 code word.
function GetCaptureControl: TControl |Returns the control, if any, that currently receives all mouse messages.
procedure GetCharsetValues(Proc: TGetStrProc) |Passes the name of every predefined character set string to a callback function.
function GetClass(const ClassName: string): TPersistentClass |Returns a registered persistent class given its name.

procedure GetColorValues(Proc: TGetStrProc) |Passes the name of every predefined color constant to a callback function.
function GetComCtlVersion: Integer |Indicates which version of ComCtl32.dll is installed.

function GetCurrentDir: string |Returns the name of the current directory.
procedure GetCursorPos(var P: TPoint) |Return mouse cursor position.
procedure GetCursorValues(Proc: TGetStrProc) |Passes the name of every predefined cursor constant to a callback.

function GetDefFontCharSet: TFontCharset |Returns the character set of the default system font.
function GetDIB(Bitmap: HBITMAP; Palette: HPALETTE; var BitmapInfo; var Bits): Boolean |Returns the info header and image for a device independent bitmap.
procedure GetDIBSizes(Bitmap: HBITMAP; var InfoHeaderSize: DWord; var ImageSize: DWORD) |Returns the size of the info header and of the image for a device independent bitmap.
procedure GetDir(D: Byte; var S: string) |Returns the name of the current directory for a specified drive.

function GetEnumName(TypeInfo: PTypeInfo; Value: Integer): string |Returns the name of a Delphi enumerated type constant given its value.
function GetEnumValue(TypeInfo: PTypeInfo; const Name: string): Integer |Returns the value of an enumerated type constant given its string representation.
function GetEnvironmentVariable(Name: string): string |Returns the value of an environment variable.
function GetExceptionMask: TFPUExceptionMask |Returns the exception mask from the FPU control word.

function GetFileVersion(const AFileName: string): Cardinal |Returns file version.
function GetFileType(Info: PFileInfo): string |Describes file.
var GetFileTypeProc: TGetFileTypeProc |Specifies procedure used describe files.

procedure GetFormatSettings |Resets the date and number format parameters to initial values.
function GetHeapStatus: THeapStatus |Returns the current status of the memory manager.
function GetHelpSystem(out System: IHelpSystem) : Integer |Returns Help System object.
function GetHotkey(const Text: string): string |Returns the last character in a string marked with an ampersand (&).

function GetLastError: Integer |Returns the last error reported by an operating system API call.
procedure GetLocaleFormatSettings(LCID: Integer; var FormatSettings: TFormatSettings) |Populates a TFormatSettings data structure based on the Windows locale ID.
function GetLongHint(const Hint: string): string |Returns the second part of a two-part hint string.
procedure GetMem(var P: Pointer; Size: Integer) |Creates a dynamic variable and a pointer to the address of the block.
procedure GetMemoryManager(var MemMgr: TMemoryManager) |Returns the entry points of the currently installed memory manager.

function GetModuleFileName(Module: HMODULE; Buffer: PChar; BufLen: Integer): Integer |Returns the fully qualified name for a module, given its handle.
function GetModuleName(Module: HMODULE): string |Returns the fully qualified name for a module, given its handle.
function GetMouseGrabControl: TControl |Returns the control, if any, that currently receives all mouse messages.
function GetParentForm(Control: TControl): TCustomForm |Returns the form that contains a specified control.
function GetPrecisionMode: TFPUPrecisionMode |Returns the FPU precision control mode.
function GetRoundMode: TFPURoundingMode |Returns the FPU rounding mode.

function GetScreen: TScreen |Returns a screen device.
function GetShortHint(const Hint: string): string |Returns the first part of a two-part hint string.
function GetTime: TDateTime |Returns the current time.
procedure GetVariantManager(var VarMgr: TVariantManager) |Returns the entry points of the routines that define variant behavior.

function GradToCycle(const Grads: Extended): Extended |Converts grad measurements to cycles.
function GradToDeg(const Grads: Extended): Extended |Converts grad measurements to degrees.
function GradToRad(const Grads: Extended): Extended |Converts grad measurements to radians.

function GraphicExtension(GraphicClass: TGraphicClass): string |Returns the default file-name extension of a graphics object.
function GraphicFileMask(GraphicClass: TGraphicClass): string |Returns a file mask that specifies the valid extensions for a graphic class.
function GraphicFilter(GraphicClass: TGraphicClass[; AllFilter: Boolean = True]): string |Returns a file filter compatible with the Filter property of an Open or Save dialog.

procedure GroupDescendantsWith(AClass, AClassGroup: TPersistentClass) |Adds a specified class to the group in which another class appears.
function GUIDToString(const ClassID: TGUID): string |Converts a class identifier GUID to a string.

procedure Halt(ExitCode: Integer) |Terminates a program abnormally.
procedure HandleConversionException(const ASourceType, ADestType: TVarType) |Handles exceptions during variant type conversions.

function HasSubDirs(const Directory: WideString; IncludeHidden: Boolean = False): Boolean |Determines if a directory contains other directories.
var HeapAllocFlags: Word |Indicates how the memory manager obtains memory from the operating system.

function High(X) |Returns the upper limit of an Ordinal, Array, or ShortString value.
function HexToBin(Text, Buffer: PChar; BufSize: Integer): Integer |Converts a string of hexadecimal digits to its binary representation.
function Hi(X): Byte |Returns the high-order byte of X as an unsigned value.

function HourOf(const AValue: TDateTime): Word |Returns the hour of the day represented by a TDateTime value.
function HourOfTheDay(const AValue: TDateTime): Word |Returns the hour of the day represented by a TDateTime value.
function HourOfTheMonth(const AValue: TDateTime): Word |Returns the number of hours between a specified TDateTime value and 12:00 AM of the first day of the month.
function HourOfTheWeek(const AValue: TDateTime): Word |Returns the number of hours between a specified TDateTime value and 12:00 AM of the first day of the week.
function HourOfTheYear(const AValue: TDateTime): Word |Returns the number of hours between a specified TDateTime value and 12:00 AM of the first day of the year.
function HoursBetween(const ANow, AThen: TDateTime): Int64 |Returns the number of whole hours between two specified TDateTime values.
function HourSpan(const ANow, AThen: TDateTime): Double |Returns the number of Hours (including fractional Hours) between two specified TDateTime values.

function Hypot(const X, Y: Extended): Extended |Calculates the length of the hypotenuse.

function IconPixels(const Size: TIconSize): Integer |Returns specific pixel dimensions for icon size.
function IconProvider16: TFileIconProvider |Returns small icon provider.
function IconProvider32: TFileIconProvider |Returns large icon provider.
function IconProvider48: TFileIconProvider |Returns very large icon provider.

function IdentToCharset(const Ident: string; var Charset: Longint): Boolean |Translates the name of a character set constant to the corresponding character set.
function IdentToColor(const Ident: string; var Color: Longint): Boolean |Translates the name of a color constant to the corresponding TColor value.
function IdentToCursor(const Ident: string; var Cursor: Longint): Boolean |Translates a predefined cursor constant into a cursor.
function IdentToInt(const Ident: string; var Int: Longint; const Map: array of TIdentMapEntry): Boolean |Uses a mapping array to convert string identifiers into their corresponding integer values.

function IfThen(AValue: Boolean; const ATrue: Integer; const AFalse: Integer = 0): Integer |Returns one of two values, depending on the evaluation of an expression.
procedure Inc(var X [; N: Longint]) |Increments an ordinal value by 1 or N.

procedure IncAMonth(var Year, Month, Day: Word; NumberOfMonths: Integer = 1) |Increments date data by one month.
function IncDay(const AValue: TDateTime; const ANumberOfDays: Integer = 1): TDateTime |Returns a date shifted by a specified number of days.
function IncHour(const AValue: TDateTime; const ANumberOfHours: Int64 = 1): TDateTime |Returns a date/time value shifted by a specified number of hours.
function IncMilliSecond(const AValue: TDateTime; const ANumberOfMilliSeconds: Int64 = 1): TDateTime |Returns a date/time value shifted by a specified number of milliseconds.
function IncMinute(const AValue: TDateTime; const ANumberOfMinutes: Int64 = 1): TDateTime |Returns a date/time value shifted by a specified number of minutes.
function IncMonth(const Date: TDateTime; NumberOfMonths: Integer = 1): TDateTime |Returns a date shifted by a specified number of months.
function IncSecond(const AValue: TDateTime; const ANumberOfSeconds: Int64 = 1): TDateTime |Returns a date/time value shifted by a specified number of seconds.
function IncWeek(const AValue: TDateTime; const ANumberOfWeeks: Integer = 1): TDateTime |Returns a date shifted by a specified number of weeks.
function IncYear(const AValue: TDateTime; const ANumberOfYears: Integer = 1): TDateTime |Returns a date shifted by a specified number of years.

procedure Include(var S: set of T; I: T) |Adds an element to a set.
function IncludeTrailingBackslash(const S: string): string |Adds '\' to the end of a string if it is not already there.
function IncludeTrailingPathDelimiter(const S: string): string |Ensures path name ends with delimiter.

const Infinity |Represents positive infinity.
function InitCommonControl(CC: Integer): Boolean |Wraps the Windows API routine, InitCommonControlsEx, which registers common control classes from ComCtl32.dll.
procedure Initialize(var V [; Count: Integer]) |Initializes a dynamically allocated variable.
function InitInheritedComponent(Instance: TComponent; RootAncestor: TClass): Boolean |Initializes streaming of a form file for an inherited root class.
var Input: Text |Specifies a read-only Text file associated with the processes standard input file.
function InputBox(const ACaption, APrompt, ADefault: string): string |Brings up an input dialog box ready for the user to enter a string in its edit box.
function InputQuery(const ACaption, APrompt: string; var Value: string): Boolean |Brings up an input dialog box ready for the user to enter a string in its edit box or to cancel the input.
function InRange(const AValue, AMin, AMax: Integer): Boolean |Returns True if a Value falls into a specified range.
procedure Insert(Source: string; var S: string; Index: Integer) |Inserts a substring into a string at a given position.
function Int(X: Extended): Extended |Returns the integer part of a number.

function InterlockedDecrement(var I: Integer): Integer |Decrements a variable in a thread-safe manner.
function InterlockedExchange(var A: Integer; B: Integer): Integer |Swaps two integer values in a thread-safe manner.
function InterlockedExchangeAdd(var A: Integer; B: Integer): Integer |Adds two integers in a thread-safe manner.
function InterlockedIncrement(var I: Integer): Integer |Increments an integer value in a thread-safe manner.

function IntersectRect(out Rect: TRect; const R1, R2: TRect): Boolean |Returns the intersection of two rectangles.
function IntPower(const Base: Extended; const Exponent: Integer): Extended |Returns a real number raised to an integer power.
function IntToHex(Value: Integer; Digits: Integer): string |Converts an integer to a string - hex representation.
function IntToIdent(Int: Longint; var Ident: string; const Map: array of TIdentMapEntry): Boolean |Uses a mapping array to convert integers into their corresponding string identifiers.
function IntToStr(Value: Integer): string |Converts an integer to a string.
function InvalidPoint(const At: TPoint): Boolean |Indicates whether a specified point is equal to (-1,-1).
function IOResult: Integer |Returns the status of the last I/O operation performed.

function IsAbortResult(const AModalResult: TModalResult): Boolean |Checks the return value from a modal form dialog and indicates whether the user selected Abort or Cancel.
function IsAccel(VK: Word; const Str: string): Boolean |Indicates whether a particular character is an accelerator character (or hot key) within a given menu caption or other text string.
function IsAnAllResult(const AModalResult: TModalResult): Boolean |Checks the return value from a modal form dialog and indicates whether the user selected All, Yes to All, or No to All.
function IsDelimiter(const Delimiters, S: string; Index: Integer): Boolean |Returns True if a specified character in a string matches one of a set of delimiters starting from some position.
function IsEqualGUID(const guid1, guid2: TGUID): Boolean |Indicates whether two TGUID values are the same.
function IsInfinite(const AValue: Double): Boolean |Returns true if the value specified represents positive or negative infinity.
function IsInLeapYear(const AValue: TDateTime): Boolean |Indicates whether a specified TDateTime value occurs in a leap year.
function IsLeapYear(Year: Word): Boolean |Indicates whether a specified year is a leap year.

function IsMemoryManagerSet: Boolean |Indicates whether the memory manager has been overridden using the SetMemoryManager procedure.
var IsMultiThread: Boolean |Indicates whether the application spawned additional threads using BeginThread or TThread objects.
function IsNan(const AValue: Extended): Boolean |Indicates when a variable or expression does not evaluate to a numeric value.
function IsNegativeResult(const AModalResult: TModalResult): Boolean |Checks the return value from a modal form dialog and indicates whether the user selected No or No to All.
function IsPathDelimiter(const S: string; Index: Integer): Boolean |Returns true if a specified character in a string is the backslash (\) character.
function IsPM(const AValue: TDateTime): Boolean |Returns true if the time portion of a TDateTime value occurs on or after 12:00 (noon) and before 24:00 (midnight).
function IsPositiveResult(const AModalResult: TModalResult): Boolean |Checks the return value from a modal form dialog and indicates whether the user selected Ok, Yes, Yes to All, or All.
function IsRectEmpty(const Rect: TRect): Boolean |Indicates wither a specified rectangle has a positive width and height.
function IsRelativePath(const Filename: string): Boolean |Determines if file name is relative.
function IsRootDirectory(const Directory: string): Boolean |Determines if string contains root directory name.
function IsSameDay(const AValue, ABasis: TDateTime): Boolean |Indicates whether a specified TDateTime value occurs on a the same day as a criterion date.
function IsToday(const AValue: TDateTime): Boolean |Indicates whether a specified TDateTime value occurs on the current date.
function IsUniqueGlobalComponentName(const Name: string): Boolean |Indicates whether a proposed component name is unambiguous.

function IsValidDate(const AYear, AMonth, ADay: Word): Boolean |Indicates whether a specified year, month, and day represent a valid date.
function IsValidDateDay(const AYear, ADayOfYear: Word): Boolean |Indicates whether a specified year and day of the year represent a valid date.
function IsValidDateMonthWeek(const AYear, AMonth, AWeekOfMonth, ADayOfWeek: Word): Boolean |Indicates whether a specified year, month, week of the month, and day of the week represent a valid date.
function IsValidDateTime(const AYear, AMonth, ADay, AHour, AMinute, ASecond, AMilliSecond: Word): Boolean |Indicates whether a specified year, month, day, hour, minute, second, and millisecond represent a valid date and time.
function IsValidDateWeek(const AYear, AWeekOfYear, ADayOfWeek: Word): Boolean |Indicates whether a specified year, week of the year, and day of the week represent a valid date.
function IsValidIdent(const Ident: string): Boolean |Tests for a valid CLX identifier.
function IsValidTime(const AHour, AMinute, ASecond, AMilliSecond: Word): Boolean |Indicates whether a specified hour, minute, second, and millisecond represent a valid date and time.
function IsVariantManagerSet: Boolean |Indicates whether variant support is implemented in an application.
function IsZero(const A: Extended; Epsilon: Extended = 0): Boolean |Indicates when a floating-point variable or expression evaluates to zero, or very close to zero.

function LastDelimiter(const Delimiters, S: string): Integer |Returns the index of the last occurence in a string of the characters specified.

var LeadBytes: set of Char |Lists all values that can be the first byte of a double byte character on the local system.
function LeftBStr(const AText: AnsiString; const AByteCount: Integer): AnsiString |Returns the substring of a specified number of bytes that appears at the start of a string.
function LeftStr(const AText: AnsiString; const ACount: Integer): string |Returns a string containing a specified number of characters from the left side of a string.
function Length(S): Integer |Returns an integer containing the number of characters in a string or the number of elements in an array.
function Ldexp(const X: Extended; const P: Integer): Extended |Calculates X times (2 to the power of P).
function LineStart(Buffer, BufPos: PChar): PChar |Finds the end of the last whole line in a buffer.
function Ln(X: Real): Real |Returns the natural logarithm of a number.
function LnXP1(const X: Extended): Extended |Returns the natural log of (X+1).
function Lo(X): byte |Returns the low order Byte of argument X.
function LoadStr(Ident: Integer): string |Loads a string resource from the application's executable file.
function Log10(const X: Extended): Extended |Calculates log base 10.
function Log2(const X: Extended): Extended |Calculates log base 2.
function LogN(const Base, X: Extended): Extended |Calculates the log of X for a specified base.
function Low(X) |Returns the lower limit of an Ordinal, Array, or ShortString value.
function LowerCase(const S: string): string |Returns a string that has been converted to lowercase.
function MatchesMask(const Filename, Mask: string): Boolean |Returns True is a string value matches a format specifed by a mask.
function Max(A, B: Integer): Integer |Returns the greater value of the two numerical values.
function MaxIntValue(const Data: array of Integer): Integer |Returns the greatest value in an integer array.
function MaxValue(const Data: array of Double): Double |Returns the greatest value in an array holding real values.

const MaxComp |The maximum value of the Comp data type.
const MaxDouble |The maximum value of the double precision floating point type.
const MaxExtended |The maximum value of the Extended data type.
const MaxDateTime: TDateTime |The maximum value of the TDateTime type.
const MaxInt |The maximum value of the Integer data type.
const MaxLongint |The maximum value of the Longint data type.
const MaxSingle |The maximum value of the single precision floating point type.

function MessageDlg(const Msg: string; DlgType: TMsgDlgType; Buttons: TMsgDlgButtons; HelpCtx: Longint): Word |Displays a message dialog box in the center of the screen.
function MessageDlgPos(const Msg: string; DlgType: TMsgDlgType; Buttons: TMsgDlgButtons; HelpCtx: Longint; X, Y: Integer): Word |Displays a message dialog box at the specified screen coordinates.
function MessageDlgPosHelp(const Msg: string; DlgType: TMsgDlgType; Buttons: TMsgDlgButtons; HelpCtx: Longint; X, Y: Integer; const HelpFileName: string): Word |Displays a message dialog box whose help is supplied in a named help file.
function MidBStr(const AText: AnsiString; const AByteStart, AByteCount: Integer): AnsiString |Returns the substring of a specified number of bytes that appears at a specified position in a string.
function MidStr(const AText: AnsiString; const AStart, ACount: Integer): AnsiString |Returns the substring of a specified length that appears at a specified position in a string.

function MilliSecondOf(const AValue: TDateTime): Word |Returns the millisecond of the second represented by a TDateTime value.
function MilliSecondOfTheDay(const AValue: TDateTime): LongWord |Returns the number of milliseconds between a specified TDateTime value and the beginning of the same day.
function MilliSecondOfTheHour(const AValue: TDateTime): LongWord |Returns the number of milliseconds between a specified TDateTime value and the beginning of the same hour.
function MilliSecondOfTheMinute(const AValue: TDateTime): LongWord |Returns the number of milliseconds between a specified TDateTime value and the beginning of the same minute.
function MilliSecondOfTheMonth(const AValue: TDateTime): LongWord |Returns the number of milliseconds between a specified TDateTime value and the beginning of the month.
function MilliSecondOfTheSecond(const AValue: TDateTime): Word |Returns the millisecond of the second represented by a TDateTime value.
function MilliSecondOfTheWeek(const AValue: TDateTime): LongWord |Returns the number of milliseconds between a specified TDateTime value and 12:00:00:00 AM of the first day of the week.
function MilliSecondOfTheYear(const AValue: TDateTime): Int64 |Returns the number of milliseconds between a specified TDateTime value and 12:00:00:00 AM of the first day of the year.
function MilliSecondsBetween(const ANow, AThen: TDateTime): Int64 |Returns the number of milliseconds between two specified TDateTime values.
function MilliSecondSpan(const ANow, AThen: TDateTime): Double |Returns the number of milliseconds between two specified TDateTime values.

function Min(A, B: Integer): Integer |Returns the smaller value of the two numerical values.
function MinimizeName(const Filename: TFileName; Canvas: TCanvas; MaxLen: Integer): TFileName |Returns a shortened version of a filename (using dots for folders) that fits into some pixel length.
function MinIntValue(const Data: array of Integer): Integer |Returns the smallest value in an integer array.

const MinComp |The minimum value of the Comp data type.
const MinDouble |The minimum value of the double precision floating point type.
const MinExtended |The minimum value of the Extended data type.
const MinDateTime: TDateTime |The minimum value of the TDateTime type.
const MinSingle |The minimum value of the single precision floating point type.

function MinuteOf(const AValue: TDateTime): Word |Returns the minute of the hour represented by a TDateTime value.
function MinuteOfTheDay(const AValue: TDateTime): Word |Returns the number of minutes between a specified TDateTime value and 12:00 AM of the same day.
function MinuteOfTheHour(const AValue: TDateTime): Word |Returns the number of minutes between a specified TDateTime value and the beginning of the same hour.
function MinuteOfTheMonth(const AValue: TDateTime): Word |Returns the number of minutes between a specified TDateTime value and 12:00 AM of the first day of the month.
function MinuteOfTheWeek(const AValue: TDateTime): Word |Returns the number of minutes between a specified TDateTime value and 12:00 AM of the first day of the week.
function MinuteOfTheYear(const AValue: TDateTime): LongWord |Returns the number of minutes between a specified TDateTime value and 12:00 AM of the first day of the year.
function MinutesBetween(const ANow, AThen: TDateTime): Int64 |Returns the number of minutes between two specified TDateTime values.
function MinuteSpan(const ANow, AThen: TDateTime): Double |Returns the number of minutes, including fractions thereof, between two specified TDateTime values.

function MinValue(const Data: array of Double): Double |Returns the smallest value in an array holding real values.
procedure MkDir(const S: string) |Creates a new subdirectory.

function MonthOf(const AValue: TDateTime): Word |Returns the month of the year represented by a TDateTime value.
function MonthOfTheYear(const AValue: TDateTime): Word |Returns the month of the year represented by a TDateTime value.
function MonthsBetween(const ANow, AThen: TDateTime): Integer |Returns the approximate number of months between two specified TDateTime values.
function MonthSpan(const ANow, AThen: TDateTime): Double |Returns the approximate number of months, including fractions, between two specified TDateTime values.

var Mouse: TMouse |Contains information about the system’s mouse.
procedure Move(const Source; var Dest; Count: Integer) |Copies bytes from a source to a destination.
procedure MoveWindowOrg(DC: HDC; DX, DY: Integer) |Changes the location of the point (0,0) within a device context.
function MSecsToTimeStamp(MSecs: Comp): TTimeStamp |Converts a specified number of milliseconds into a TTimeStamp value.
function MulDiv(Number, Numerator, Denominator: Integer): Integer |Peforms a specified integer multiplication followed by a specified integer division.

const NaN |Represents a value that is not a number in Delphi.
const NegInfinity |Represents negative infinity in Delphi.
procedure New(var P: Pointer) |Creates a new dynamic variable and sets P to point to it.

function NewItem(const ACaption: string; AShortCut: TShortCut; AChecked, AEnabled: Boolean; AOnClick: TNotifyEvent; hCtx: THelpContext; const AName: string): TMenuItem |Creates and initializes a menu item.
function NewLine: TMenuItem |Creates a menu item for a separator.
function NewMenu(Owner: TComponent; const AName: string; const Items: array of TMenuItem): TMainMenu |Creates and initializes a main menu.
function NewPopupMenu(Owner: TComponent; const AName: string; Alignment: TPopupAlignment; AutoPopup: Boolean; const Items: array of TMenuItem): TPopupMenu |Creates and initializes a popup menu.
function NewStr(const S: string): PString; deprecated |Allocates a string on the heap.
var NewStyleControls: Boolean |Determines whether controls are drawn using the Windows 3.x “look”.
function NewSubMenu(const ACaption: string; hCtx: THelpContext; const AName: string; const Items: array of TMenuItem; AEnabled: Boolean = True): TMenuItem |Creates and initializes a menu item that represents a submenu.
function NextCharIndex(const S: String; Index: Integer): Integer |Returns the byte index of the next character.

function Now: TDateTime |Returns the current system date and time.
function NthDayOfWeek(const AValue: TDateTime): Word |Returns which occurrence of its weekday a specified TDateTime value represents.

function Null: Variant |Returns a Null variant.
var NullAsStringValue: string |Specifies string value of Null variants.
var NullEqualityRule: TNullCompareRule |Specifies rule for Null variant equality comparison.
var NullMagnitudeRule: TNullCompareRule |Specifies rule for Null variant magnitude comparison.
const NullSQLTimeStamp: TSQLTimeStamp |Represents a NULL TSQLTimeStamp value.
const NullStr: PString |Declares a pointer to an empty string.
var NullStrictConvert: Boolean |Specifies whether Null conversion is an error.

procedure ObjectBinaryToText(Input, Output: TStream[; var OriginalFormat: TStreamOriginalFormat]) |Converts the binary representation of an object into more readily understandable text.
procedure ObjectResourceToText(Input, Output: TStream[; var OriginalFormat: TStreamOriginalFormat]) |Converts the binary representation of an object resource into more readily understandable text.
procedure ObjectTextToBinary(Input, Output: TStream[; var OriginalFormat: TStreamOriginalFormat]) |Converts a symbolic text representation of an object into the binary version that is used to save the object to files or memory streams.
procedure ObjectTextToResource(Input, Output: TStream[; var OriginalFormat: TStreamOriginalFormat]) |Converts a symbolic text representation of an object into an internal binary representation.

function Odd(X: Longint): Boolean |Returns True if a given integer value is an odd number.
function OffsetRect(var Rect: TRect; DX: Integer; DY: Integer): Boolean |Changes the origin of a rectangle by a specified amount.

const OneHour: TDateTime |1 / HoursPerDay
const OneMillisecond: TDateTime |1 / MSecsPerDay
const OneMinute: TDateTime |1 / MinsPerDay
const OneSecond: TDateTime |1 / SecsPerDay

function Ord(X): Integer |Returns an Integer representing the ordinal value of an ordinal value.
procedure OutOfMemoryError |Raises an EOutOfMemory exception.
var Output: Text |Specifies a write-only Text file associated with the process's standard output file.

var PackVarCreation: Boolean |Specifies whether space-efficient Variant Types are preferred.
function ParamCount: Integer |Returns the number of command-line parameters.
function ParamStr(Index: Integer): string |Returns the specified command-line parameter.
function Pi: Extended |Returns the number: 3.1415...
function Point(AX, AY: Integer): TPoint |Returns the Point type variable from two integers.
function PointsEqual(const P1, P2: TPoint): Boolean |Indicates whether two points have the same coordinates.
function Poly(const X: Extended; const Coefficients: array of Double): Extended |Evaluates a uniform polynomial of one variable at the value X.
function Pos(Substr: string; S: string): Integer |Returns an integer specifying the position of the first occurrence of one string within another.
function PosEx(const SubStr, S: string; Offset: Cardinal = 1): Integer |Returns an integer specifying the position of the first occurrence of one string within another, where the search starts at a specified position.
function Power(const Base, Exponent: Extended): Extended |Returns a real number raised any power.
function Pred(X) |Returns the predecessor of the ordinal value.

function Printer: TPrinter |Returns a global instance of TPrinter to manage interaction with the printer.
procedure ProcessPath(const EditText: string; var Drive: Char; var DirPart: string; var FilePart: string) |Parses a full file name into its drive, path, and file name.
function PromptForFileName(var AFileName: string; const AFilter: string = ''; const ADefaultExt: string = ''; const ATitle: string = ''; const AInitialDir: string = ''; SaveDialog: Boolean = False): Boolean |Displays an open or save dialog, enabling the user to select or specify a file name.
function PtInRect(const Rect: TRect; const P: TPoint): Boolean |Returns true if a specified point lies inside a specified rectangle.
function Ptr(Address: Integer): Pointer |Converts a specified address to an untyped pointer.
function QuotedStr(const S: string): string |Returns the quoted version of a string.

procedure RaiseLastOSError |Raises an exception for the last occurring OS or system library error.
procedure RaiseLastWin32Error |Raises an exception for the last occurring Win32 error.

function RandG(Mean, StdDev: Extended): Extended |Generates random numbers with Gaussian distribution.
function Random(Range: Integer): Integer |Returns a randomly generated number within a specified range.
function RandomFrom(const AValues: array) |Returns an element at random position from an array.
procedure Randomize |Initializes the random number generator.
function RandomRange(const AFrom, ATo: Integer): Integer |Returns a random integer from a specified range.
var RandSeed: Longint |Stores the built-in random number generator's seed.

procedure Read(F, V1 [, V2,...,Vn]) |Read reads data from a file.
function ReadComponentRes(const ResName: string; Instance: TComponent): TComponent |Reads components and their properties from a specified resource.
function ReadComponentResEx(HInstance: THandle; const ResName: string): TComponent |Reads a component from a resource.
function ReadComponentResFile(const FileName: string; Instance: TComponent): TComponent |Reads components and their properties from a specified Windows resource file.
procedure ReadLn([var F: Text;] V1 [, V2, ...,Vn]) |Reads a line of text from a file.
procedure ReallocMem(var P: Pointer; Size: Integer) |Reallocates a dynamic variable.

function RecodeDate(const AValue: TDateTime; const AYear, AMonth, ADay: Word): TDateTime |Replaces the date portion of a specified TDateTime value.
function RecodeDateTime(const AValue: TDateTime; const AYear, AMonth, ADay, AHour, AMinute, ASecond, AMilliSecond: Word): TDateTime |Selectively replaces parts of a specified TDateTime value.
function RecodeDay(const AValue: TDateTime; const ADay: Word): TDateTime |Replaces the day of the month for a specified TDateTime value.
function RecodeHour(const AValue: TDateTime; const AHour: Word): TDateTime |Replaces the hour of the day for a specified TDateTime value.
const RecodeLeaveFieldAsIs |Flag for RecodeDateTime function.
function RecodeMilliSecond(const AValue: TDateTime; const AMilliSecond: Word): TDateTime |Replaces the millisecond of the second for a specified TDateTime value.
function RecodeMinute(const AValue: TDateTime; const AMinute: Word): TDateTime |Replaces the minute of the hour for a specified TDateTime value.
function RecodeMonth(const AValue: TDateTime; const AMonth: Word): TDateTime |Replaces the month of the year for a specified TDateTime value.
function RecodeSecond(const AValue: TDateTime; const ASecond: Word): TDateTime |Replaces the second of the minute for a specified TDateTime value.
function RecodeTime(const AValue: TDateTime; const AHour, AMinute, ASecond, AMilliSecond: Word): TDateTime |Replaces the time portion of a specified TDateTime value.
function RecodeYear(const AValue: TDateTime; const AYear: Word): TDateTime |Replaces the year for a specified TDateTime value.
function Rect(ALeft, ATop, ARight, ABottom: Integer): TRect |Returns the TRect type variable from a rectangle given with top-left and bottom-right coordinate.

procedure RegisterActions(const CategoryName: string; const AClasses: array of TBasicActionClass; Resource: TComponentClass) |Registers action classes so that they appear in the list of predefined actions in the action list editor or customize dialog.
procedure RegisterActnBarStyle(AStyle: TActionBarStyleEx) |egisters an action band style so that it is available for use from TActionManager's Style property within the IDE.
procedure RegisterClass(AClass: TPersistentClass) |Registers a class of persistent object so that it’s class type can be retrieved.
procedure RegisterClassAlias(AClass: TPersistentClass; const Alias: string) |Registers a class that is identical to another class except for the name.
procedure RegisterClasses(AClasses: array of TPersistentClass) |Registers a set of classes.

procedure RegisterComponents(const Page: string; const ComponentClasses: array of TComponentClass) |Registers a set of components so that they all appear on the same page of the component palette.
procedure RegisterFields(const FieldClasses: array of TFieldClass) |Registers a set of field components so that they appear in the Dataset designer.
procedure RegisterIntegerConsts(AIntegerType: Pointer; AIdentToInt: TIdentToInt; AIntToIdent: TIntToIdent) |Registers conversion functions for string identifiers that represent type values.
procedure RegisterNoIcon(const ComponentClasses: array of TComponentClass) |Registers a set of components but does not add them to the component palette.
procedure RegisterNonActiveX(const ComponentClasses: array of TComponentClass; AxRegType: TActiveXRegType) |Prevents a set of components from being made available to the ActiveX wizard.
procedure RegisterPackageWizard(const Wizard: IOTAWizard); |Registers a wizard instance with the IDE.
function RegisterViewer(const newViewer: ICustomHelpViewer; out Manager: IHelpManager): Integer |Register Help Viewer to receive requests.

procedure ReleaseExceptionObject |Releases exception object acquired by AcquireExceptionObject.
function RemoveDir(const Dir: string): Boolean |Deletes an empty folder.
procedure Rename(var F; NewName: string) |Changes the name of an external file.
function RenameFile(const OldName, NewName: string): Boolean |Changes the name of a specified file.

procedure ReplaceDate(var DateTime: TDateTime; const NewDate: TDateTime) |Replaces the date portion of a TDateTime value with a specified date.
procedure ReplaceTime(var DateTime: TDateTime; const NewTime: TDateTime) |Replaces the time portion of a TDateTime value with a specified time.
procedure Reset(var F: File[; RecSize: Word]) |Opens an existing file.
var Result |Result of the current function.
function ReverseString(const AText: string): string |Returns a string in which the character order of a specified string is reversed.
procedure Rewrite(var F: File[; Recsize: Word]) |Creates a new file and opens it.
function RightBStr(const AText: AnsiString; const AByteCount: Integer): AnsiString |Returns the substring of a specified number of bytes that appears at the end of a string.
function RightStr(const AText: string; const ACount: Integer): string |Returns a string containing a specified number of characters from the right side of a string.
procedure RmDir(const S: string) |Deletes an empty subdirectory.
function Round(X: Extended): Int64 |Returns the value of X rounded to the nearest whole number.
function RoundTo(const AValue: Double; const ADigit: TRoundToRange): Double |Rounds a floating-point value to a specified digit or power of ten using “Banker’s rounding”.
procedure RunError(ErrorCode: Byte) |Stops execution and generates a runtime error.

function SameDate(const A, B: TDateTime): Boolean |Indicates whether two TDateTime values represent the same year, month, and day.
function SameDateTime(const A, B: TDateTime): Boolean |Indicates whether two TDateTime values represent the same year, month, day, hour, minute, second, and millisecond.
function SameFileName(const S1, S2: string): Boolean |Compares file names based on the current locale.
function SameTime(const A, B: TDateTime): Boolean |Indicates whether two TDateTime values represent the same time of day, ignoring the date portion.
function SameValue(const A, B: Extended; Epsilon: Extended = 0): Boolean |Indicates whether two floating-point values are (approximately) equal.

function SearchBuf(Buf: PChar; BufLen: Integer; SelStart, SelLength: Integer; SearchString: String; Options: TStringSearchOptions = [soDown]): PChar |Locates a substring within a text buffer.

function Sec(const X: Extended): Extended |Calculates the secant of an angle.
function Secant(const X: Extended): Extended |Calculates the secant of an angle.
function SecH(const X: Extended): Extended |Calculates the hyperbolic secant of an angle.

function SecondOf(const AValue: TDateTime): Word |Returns the second of the minute represented by a TDateTime value.
function SecondOfTheDay(const AValue: TDateTime): LongWord |Returns the number of seconds between a specified TDateTime value and 12:00:00 AM of the same day.
function SecondOfTheHour(const AValue: TDateTime): Word |Returns the number of seconds between a specified TDateTime value and the beginning of the same hour.
function SecondOfTheMinute(const AValue: TDateTime): Word |Returns the number of seconds between a specified TDateTime value and the beginning of the same minute.
function SecondOfTheMonth(const AValue: TDateTime): LongWord |Returns the number of seconds between a specified TDateTime value and 12:00:00 AM on the first day of the month.
function SecondOfTheWeek(const AValue: TDateTime): LongWord |Returns the number of seconds between a specified TDateTime value and 12:00:00 AM of the first day of the week.
function SecondOfTheYear(const AValue: TDateTime): LongWord |Returns the number of seconds between a specified TDateTime value and 12:00:00 AM on the first day of the year.
function SecondsBetween(const ANow, AThen: TDateTime): Int64 |Returns the number of seconds between two specified TDateTime values.
function SecondSpan(const ANow, AThen: TDateTime): Double |Returns the number of seconds (including fractions thereof) between two specified TDateTime values.

procedure Seek(var F; N: Longint) |Moves the current position of a file to a specified component.
function SeekEof([var F: Text]): Boolean |Returns the end-of-file status of a file, ignoring whitespace.
function SeekEoln([var F: Text]): Boolean |Returns the end-of-line status of a file, ignoring whitespace.

function SelectDirectory(const Caption: string; const Root: WideString; out Directory: string): Boolean |Brings up a dialog box ready for the user to select a directory name.
function SendAppMessage(Msg: Cardinal; WParam, LParam: Longint): Longint |Sends a Windows message to the application.

procedure Set8087CW(NewCW: Word) |Sets both the control word in the floating point unit and the variable NoErrMsg declared in the system unit.
procedure SetCaptureControl(Control: TControl) |Causes the specified control to receive all mouse messages.
function SetClipboard(NewClipboard: TClipboard): TClipboard |Replaces the single global clipboard instance with another clipboard object.
function SetCurrentDir(const Dir: string): Boolean |Sets the current directory.
function SetExceptionMask(const Mask: TFPUExceptionMask): TFPUExceptionMask |Sets the exception mask on the FPU control word.

procedure SetLength(var S; NewLength: Integer) |Changes the size of a dynamic array or a string.
procedure SetLineBreakStyle(var F: Text; Style: TTextLineBreakStyle) |Determines the end-of-line and end-of-file conventions for text file I/O.
procedure SetMemoryManager(const MemMgr: TMemoryManager) |Sets entry points of the memory manager.
procedure SetMouseGrabControl(Control: TControl) |Causes the specified control to receive all mouse messages.

function SetPrecisionMode(const Precision: TFPUPrecisionMode): TFPUPrecisionMode |Sets the FPU precision control mode.
function SetPrinter(NewPrinter: TPrinter): TPrinter |Replaces the global instance of TPrinter that manages interaction with the printer.

function SetRoundMode(const RoundMode: TFPURoundingMode): TFPURoundingMode |Sets the FPU rounding mode.
procedure SetString(var s: string; buffer: PChar; len: Integer) |Sets the lenght and contents of a given string.
procedure SetTextBuf(var F: Text; var Buf [; Size: Integer]) |Assigns an I/O buffer to a text file.
procedure SetVariantManager(const VarMgr: TVariantManager) |Sets the entry points of routines that define variant behavior.

function ShortCut(Key: Word; Shift: TShiftState): TShortCut |Creates a menu shortcut for a specified key combination.
procedure ShortCutToKey(ShortCut: TShortCut; var Key: Word; var Shift: TShiftState) |Returns the key code and shift state of a menu shortcut.
function ShortCutToText(ShortCut: TShortCut): string |Converts a menu shortcut into a string that describes the shortcut.

procedure ShowException(ExceptObject: TObject; ExceptAddr: Pointer) |Displays an exception message with its physical address.
procedure ShowMessage(const Msg: string) |Displays a message in a dialog box, waits for the user to click an OK button.
procedure ShowMessageFmt(const Msg: string; Params: array of const) |Displays formated message in a dialog box, waits for the user to click an OK button.
procedure ShowMessagePos(const Msg: string; X, Y: Integer) |Displays a message box at a specified location.
function Sign(const AValue: Integer): TValueSign |Indicates whether a numeric value is positive, negative, or zero.
function SimpleRoundTo(const AValue: Double; const ADigit: TSimpleRoundToRange = -2): Double |Rounds a floating-point value to a specified digit or power of ten using asymmetric arithmetic rounding.

function Sin(const X: Extended): Extended |Returns the sine of the angle in radians.
procedure SinCos(const Theta: Extended; var Sin, Cos: Extended) |Returns sine and cosine of an angle.
function Sinh(const X: Extended): Extended |Returns the hyperbolic sine of an angle.

function SizeOf(X): Integer |Returns the number of bytes occupied by a variable or type.
procedure Sleep(milliseconds: Cardinal) |Pauses program execution for a specified number of milliseconds.
function Slice(var A: array; Count: Integer): array |Returns a sub-section of an array.
function SmallPoint(AX, AY: SmallInt): TSmallPoint |Creates a TSmallPoint structure from a pair of coordinates.

function SoundEx(const AText: string; ALength: TSoundExLength  = 4): string |Converts a string into its SoundEx representation.
function SoundExCompare(const AText, AOther: string; ALength: TSoundExLength = 4): Integer |Compares the SoundEx representations of two strings.
function SoundExInt(const AText: string; ALength: TSoundExIntLength = 4): Integer |Converts a string into an integer that represents its phonetic value.
function SoundExProc(const AText, AOther: string): Boolean |Indicates whether two strings are similar.
function SoundExSimilar(const AText, AOther: string; ALength: TSoundExLength = 4): Boolean |Indicates whether two strings are similar.
function SoundExWord(const AText: string): Word |Converts a string into a Word that represents its phonetic value.

function SQLDayOfWeek(const DateTime: TSQLTimeStamp): Integer |Indicates the day of the week when a specified TSQLTimeStamp value occurs.
function SQLTimeStampToDateTime(const DateTime: TSQLTimeStamp): TDateTime |Converts a TSQLTimeStamp value to a TDateTime value.
function SQLTimeStampToStr(const Format: string; DateTime: TSQLTimeStamp): string |Converts a TSQLTimeStamp value to a string.
function Sqr(X: Extended): Extended |Returns the square of a number.
function Sqrt(X: Extended): Extended |Returns the square root of a number.

procedure StartClassGroup(AClass: TPersistentClass) |Starts a class group derived from TPersistent.

function StartOfADay(const AYear, AMonth, ADay: Word): TDateTime |Returns a TDateTime that represents 12:00:00:00 AM on a specified day.
function StartOfAMonth(const AYear, AMonth: Word): TDateTime |Returns a TDateTime that represents 12:00:00:00 AM on the first day of a specified month.
function StartOfAWeek(const AYear, AWeekOfYear: Word; const ADayOfWeek: Word = 1): TDateTime |Returns a TDateTime that represents 1the first moment on a specified day of a specified week.
function StartOfAYear(const AYear: Word): TDateTime |Returns a TDateTime that represents the first moment on the first day of a specified year.
function StartOfTheDay(const AValue: TDateTime): TDateTime |Returns a TDateTime that represents 12:00:00:00 AM on the day identified by a specified TDateTime.
function StartOfTheMonth(const AValue: TDateTime): TDateTime |Returns a TDateTime that represents 12:00:00:00 AM on the first day of the month identified by a specified TDateTime.
function StartOfTheWeek(const AValue: TDateTime): TDateTime |Returns a TDateTime that represents 12:00:00:00 AM on the first day of the week identified by a specified TDateTime.
function StartOfTheYear(const AValue: TDateTime): TDateTime |Returns a TDateTime that represents 12:00:00:00 AM on the first day of the year identified by a specified TDateTime.

procedure Str(X [: Width [: Decimals ]]; var S) |Formats a string from an integer or floating point variable.
function StrAlloc(Size: Cardinal): PChar |Allocates a buffer for a null-terminated string and returns a pointer to its first character.
function StrBufSize(const Str: PChar): Cardinal |Returns the maximum number of characters that can be stored in a buffer allocated by StrAlloc.
function StrByteType(Str: PChar; Index: Cardinal): TMbcsByteType |Indicates whether a byte in a string is a single byte character, the first byte of a double byte character, or the second byte of a double byte character.
function StrCat(Dest: PChar; const Source: PChar): PChar |Appends a copy of Source to the end of Dest and returns the concatenated string.
function StrCharLength(const Str: PChar): Integer |Returns the length, in bytes, of a character.
function StrComp(const Str1, Str2 : PChar): Integer |Compares two strings with case sensitivity.
function StrCopy(Dest: PChar; const Source: PChar): PChar |Copies a null-terminated string.
procedure StrDispose(Str: PChar) |Disposes of a string.
function StrECopy(Dest: PChar; const Source: PChar): PChar |Copies null-terminated string.
function StrEnd(const Str: PChar): PChar |Returns a pointer to the end of a null terminated string.
function StrFmt(Buffer, Format: PChar; const Args: array of const[; const FormatSettings: TFormatSettings]): PChar |Formats entries in an array.
function StrIComp(const Str1, Str2 : PChar): Integer |Compares two strings without case sensitivity.
function StringOfChar(Ch: Char; Count: Integer): string |Returns a string containing a repeating character string of the length specified.
function StringReplace(const S, OldPattern, NewPattern: string; Flags: TReplaceFlags): string |Returns a string in which a specified substring has been replaced with another substring.
function StringToColor(const S: string): TColor |Translates a string representation of a color to the corresponding TColor value.
function StringToCursor(const S: string): TCursor |Returns a TCursor value given its string representation.
function StringToGUID(const S: string): TGUID |Converts a string to a GUID.
function StripAllFromResult(const AModalResult: TModalResult): TModalResult |Converts a TModalResult value from a constant that refers to “all” to the corresponding simple constant.
function StripHotKey(const Text: string): string |Removes the accelerator character marker from a string.

function StrLCat(Dest: PChar; const Source: PChar; MaxLen: Cardinal): PChar |Appends up to a specified maximum number of characters to string.
function StrLComp(const Str1, Str2: PChar; MaxLen: Cardinal): Integer |Compares up to a specified maximum number of characters in two strings.
function StrLCopy(Dest: PChar; const Source: PChar; MaxLen: Cardinal): PChar |Copies up to a specified maximum number of characters from Source to Dest.
function StrLen(const Str: PChar): Cardinal |Returns number of characters in a string excluding the null terminator.
function StrLFmt(Buffer: PChar; MaxLen: Cardinal; Format: PChar; const Args: array of const[; const FormatSettings: TFormatSettings]): PChar |Formats a series of arguments from a specified open array into a buffer.
function StrLIComp(const Str1, Str2: PChar; MaxLen: Cardinal): Integer |Compares strings up to a specified maximum number of characters, without case sensitivity.
function StrLower(Str: PChar): PChar |Converts a string to lowercase.
function StrMove(Dest: PChar; const Source: PChar; Count: Cardinal): PChar |Copies specified number of characters to string.
function StrNew(const Str: PChar): PChar |Allocates space on and copies a string to the heap; returning a pointer to the string.
function StrNextChar(const Str: PChar): PChar |Returns pointer to following character.
function StrPas(const Str: PChar): string |Converts null-terminated string to an AnsiString (long string).
function StrPCopy(Dest: PChar; const Source: string): PChar |Copies an AnsiString (long string) to a null-terminated string.
function StrPLCopy(Dest: PChar; const Source: string; MaxLen: Cardinal): PChar |Copies characters from an AnsiString (long string) into a null-terminated string.
function StrPos(const Str1, Str2: PChar): PChar |Returns a pointer to the first occurrence of STR2 in STR1.
function StrRScan(const Str: PChar; Chr: Char): PChar |Returns a pointer to the last occurrence of a specified character in a string.
function StrScan(const Str: PChar; Chr: Char): PChar |Returns a pointer to first occurrence of a specified character in a string.

function StrToBool(const S: string): Boolean |Returns a boolean from a string value, if *possible*.
function StrToBoolDef(const S: string; const Default: Boolean): Boolean |Returns a boolean from a string value, on error returns Default.
function StrToCurr(const S: string; const FormatSettings: TFormatSettings): Currency |Converts a string to a Currency value.
function StrToCurrDef(const S: string; const Default: Currency[; const FormatSettings: TFormatSettings]): Currency |Converts a string to a Currency value, with error default.
function StrToDate(const S: string): TDateTime |Converts a string to a TDateTime value.
function StrToDateDef(const S: string; const Default: TDateTime): TDateTime |Converts a string to a TDateTime value, with error default.
function StrToDateTime(const S: string): TDateTime |Converts a string to a TDateTime value.
function StrToDateTimeDef(const S: string; const Default: TDateTime[; const FormatSettings: TFormatSettings]): TDateTime |Converts a string to a TDateTime value with error default.
function StrToInt(const S: string): Integer |Converts a string to an integer, if possible.
function StrToIntDef(const S: string; const Default: Integer): Integer |Converts a string to an integer, on error returns Default.
function StrToInt64(const S: string): Int64 |Converts a string that represents an integer (decimal or hex notation) to a number.
function StrToInt64Def(const S: string; Default: Int64): Int64 |Converts a string that represents an integer (decimal or hex notation) to a number.
function StrToFloat(const S: string[; const FormatSettings: TFormatSettings]): Extended |Returns a floating point value from a string.
function StrToFloatDef(const S: string; const Default: Extended[; const FormatSettings: TFormatSettings]): Extended |Converts a given string to a floating-point value with error default.
function StrToSQLTimeStamp(const S: string): TSQLTimeStamp |Converts a string to a TSQLTimeStamp value.
function StrToTime(const S: string[; const FormatSettings: TFormatSettings]): TDateTime |Converts a string to a TDateTime value.
function StrToTimeDef(const S: string; const Default: TDateTime[; const FormatSettings: TFormatSettings]): TDateTime |Converts a string to a TDateTime value with error default.

function StrUpper(Str: PChar): PChar |Returns a string in upper case.
function StuffString(const AText: string; AStart, ALength: Cardinal; const ASubText: string): string |Inserts a substring into a specified position of a string, replacing the current characters.

function Succ(X) |Returns the successor of the ordinal value.
function Supports(const Instance: IInterface; const IID: TGUID; out Intf): Boolean |Indicates whether a given object or interface supports a specified interface.
function Swap(X) |Exchanges high order byte with the low order byte of an integer or word.

function SysErrorMessage(ErrorCode: Integer): string |Converts OS error codes into strings.
function SysFreeMem(P: Pointer): Integer |Frees the memory pointed to by a specified pointer.
function SysGetMem(Size: Integer): Pointer |Allocates a specified number of bytes and returns a pointer to them.
function SysReallocMem(P: Pointer; Size: Integer): Pointer |Returns a pointer to a specified number of bytes, preserving the values pointed to by the Pointer parameter.
var SystemPalette16: HPalette |Contains the 16 VGA system colors.
function SystemTimeToDateTime(const SystemTime: TSystemTime): TDateTime |Converts a system time value into a TDateTime value.

function Tan(const X: Extended): Extended |Returns the tangent of X.
function Tanh(const X: Extended): Extended |Returns the hyperbolic tangent of X.

function TestStreamFormat(Stream: TStream): TStreamOriginalFormat |Identifies the format of a form file when reading it from a stream.
function TextToFloat(Buffer: PChar; var Value; ValueType: TFloatValue[; const FormatSettings: TFormatSettings]): Boolean |Converts a null-terminated string to a floating-point value.
function TextToShortCut(Text: string): TShortCut |Creates a menu shortcut from a text string.

function Time: TDateTime |Returns the current system time.
function TimeOf(const AValue: TDateTime): TDateTime |Returns only the Time portion of the TDateTime value, by setting Date part to 0.
function TimeStampToDateTime(const TimeStamp: TTimeStamp): TDateTime |Converts a TTimeStamp value into the corresponding TDateTime value.
function TimeStampToMSecs(const TimeStamp: TTimeStamp): Comp |Converts a TTimeStamp value into an absolute number of milliseconds.
function TimeToStr(Time: TDateTime[; const FormatSettings: TFormatSettings]): string |Converts a TDateTime value to a string (time part).

function Today: TDateTime |Returns a TDateTime value that represents the current date.
function Tomorrow: TDateTime |Returns a TDateTime value that represents the following day.
function Trim(const S: string): string |Returns a string containing a copy of a specified string without both leading and trailing spaces and control characters.
function TrimLeft(const S: string): string |Returns a string containing a copy of a specified string without leading spaces and control characters.
function TrimRight(const S: string): string |Returns a string containing a copy of a specified string without trailing spaces and control characters.

var TrueBoolStrs: array of String |Lists strings that can represent the boolean value True.
function Trunc(X: Extended): Int64 |Truncates a real number to an integer number.
procedure Truncate(var F) |Deletes all the records after the current file position.

function TryEncodeDate(Year, Month, Day: Word; out Date: TDateTime): Boolean |Creates a TDateTime value that represents a specified Year, Month, and Day.
function TryEncodeDateDay(const AYear, ADayOfYear: Word; out AValue: TDateTime): Boolean |Calculates the TDateTime value that represents a specified day of the year for a specified year.
function TryEncodeDateMonthWeek(const AYear, AMonth, AWeekOfMonth, ADayOfWeek: Word; out AValue: TDateTime): Boolean |Calculates the TDateTime value that represents a specified day of a specified week in a specified month and year.
function TryEncodeDateTime(const AYear, AMonth, ADay, AHour, AMinute, ASecond, AMilliSecond: Word; out AValue: TDateTime): Boolean |Calculates the TDateTime value that represents a specified year, month, day, hour, minute, second, and millisecond.
function TryEncodeDateWeek(const AYear, AWeekOfYear: Word; out AValue: TDateTime; const ADayOfWeek: Word = 1): Boolean |Calculates the TDateTime value that represents a specified day of a specified week in a specified year.
function TryEncodeDayOfWeekInMonth(const AYear, AMonth, ANthDayOfWeek, ADayOfWeek: Word, out AValue: TDateTime): Boolean |Calculates a TDateTime that represents a specified occurrence of a day of the week within a specified month and year.
function TryEncodeTime(Hour, Min, Sec, MSec: Word; out Time: TDateTime): Boolean |Creates a TDateTime value for a specified Hour, Min, Sec, and MSec.

function TryFloatToCurr(const Value: Extended; out AResult: Currency): Boolean |Converts a floating-point value to a Currency value.
function TryFloatToDateTime(const Value: Extended; out AResult: TDateTime): Boolean |Converts a floating-point value to a TDateTime value.
function TryJulianDateToDateTime(const AValue: Double; out ADateTime: TDateTime): Boolean |Converts a Julian date to a TDateTime value.
function TryModifiedJulianDateToDateTime(const AValue: Double; out ADateTime: TDateTime): Boolean |Converts a modified Julian date to a TDateTime value.

function TryRecodeDateTime(const AValue: TDateTime; const AYear, AMonth, ADay, AHour, AMinute, ASecond, AMilliSecond: Word; out AResult: TDateTime): Boolean |Selectively replaces parts of a specified TDateTime value.
function TryStrToBool(const S: string; out Value: Boolean): Boolean |Converts a string to a boolean value with a boolean success code.
function TryStrToCurr(const S: string; out Value: Currency): Boolean |Converts a string to a Currency value, with a Boolean success code.
function TryStrToDate(const S: string; out Value: TDateTime): Boolean |Converts a string to a TDateTime value, with a Boolean success code.
function TryStrToDateTime(const S: string; out Value: TDateTime): Boolean |Converts a string to a TDateTime value with a Boolean success code.
function TryStrToFloat(const S: string; out Value: Extended): Boolean |Converts a given string to a floating-point value with a boolean success code.
function TryStrToInt(const S: string; out Value: Integer): Boolean |Converts a string to an integer, returns False if string does not represent a valid number.
function TryStrToInt64(const S: string; out Value: Int64): Boolean |Converts a string that represents an integer (decimal or hex notation) to a number.
function TryStrToSQLTimeStamp(const S: string; var TimeStamp: TSQLTimeStamp): Boolean |Converts a string to a TSQLTimeStamp value.
function TryStrToTime(const S: string; out Value: TDateTime): Boolean |Converts a string to a TDateTime value with a boolean success code.

function TypeInfo(TypeIdent): Pointer |Returns a pointer to compiler-generated runtime type information for a type identifier.

function Unassigned: Variant |Returns an "empty" variant.
function UnionRect(out Rect: TRect; const R1, R2: TRect): Boolean |Returns the union of two rectangles.
procedure UniqueString(var S: string) |Ensures that a given string has a reference count of one.
const UnixDateDelta |Specifies the difference between TDateTime and TIME_T values.

procedure UnRegisterActions(const AClasses: array of TBasicActionClass) |Unregisters a set of actions.
procedure UnRegisterActnBarStyle(AStyle: TActionBarStyleEx) |nregisters an action band style from the IDE.
procedure UnregisterClass(AClass: TPersistentClass) |Unregisters an object class.
procedure UnregisterClasses(AClasses: array of TPersistentClass) |Unregisters a set of classes.
procedure UnregisterIntegerConsts(AIntegerType: Pointer; AIdentToInt: TIdentToInt; AIntToIdent: TIntToIdent) |Unregisters conversion functions for string identifiers that represent type values.
procedure UnregisterModuleClasses(Module: HMODULE) |Unregisters all classes defined in a specified module.

function UpCase(Ch: Char): Char |Converts a character to uppercase.
function UpperCase(const S: string): string |Returns a string that has been converted to uppercase.

function UTF8Decode(const S: UTF8String): WideString |Converts a UTF8 string to a Unicode string (WideString).
function UTF8Encode(const WS: WideString): UTF8String |Converts a WideString value to a UTF8 string.
function Utf8ToAnsi(const S: UTF8String): string |Converts a UTF8 string to a string of Ansi characters.
function Utf8ToUnicode(Dest: PWideChar; MaxDestChars: Cardinal; Source: PChar; SourceBytes: Cardinal): Cardinal |Converts a string of UTF-8 characters to a Unicode string.

procedure Val(S; var V; var Code: Integer) |Converts a string to a numeric value.
var ValidMenuHotkeys: string |Determines what accelerator keys can be automatically assigned to a menu item caption.
function ValidParentForm(Control: TControl): TCustomForm |Returns the form or property page that contains a specified control.

function VarArrayCreate(const Bounds: array of Integer; VarType: TVarType): Variant |Creates a variant array.
procedure VarArrayCreateError |Indicates an array creation error.
function VarArrayDimCount(const A: Variant): Integer |Returns number of dimensions of a variant array.
function VarArrayFromStrings(Strings: TStrings): Variant |Creates a Variant array that contains the strings in a TStrings object.
function VarArrayGet(const A: Variant; const Indices: array of Integer): Variant |Returns a Variant that represents a single value from a multi-dimensional Variant array.
function VarArrayHighBound(const A: Variant; Dim: Integer): Integer |Returns high bound for a dimension in a variant array.
function VarArrayLock(const A: Variant): Pointer |Locks a variant array and returns a pointer to the data.
function VarArrayLowBound(const A: Variant; Dim: Integer): Integer |Returns the low bound of a dimension in a variant array.
function VarArrayOf(const Values: array of Variant): Variant |Creates and fills a one-dimensional variant array.
procedure VarArrayPut(var A: Variant; const Value: Variant; const Indices: array of Integer) |Sets the value of a single cell in a multi-dimensional Variant array.
procedure VarArrayRedim(A: Variant; HighBound: Integer) |Resizes a Variant array.
function VarArrayRef(const A: Variant): Variant |Returns a reference to the specified variant array.
procedure VarArrayUnlock(var A: Variant) |Unlocks a variant array.
function VarAsComplex(const AValue: Variant): Variant |Casts an arbitrary Variant so that it is a custom Variant representing a complex number.
function VarAsConvert(const AValue: Variant[; const AType: TConvType]): Variant |Casts an arbitrary Variant so that it is a custom Variant representing a measurement.
function VarAsError(AResult: HRESULT): Variant |Converts a HRESULT into an Error variant.
function VarAsType(const V: Variant; VarType: TVarType): Variant |Converts a variant to specified type.
procedure VarCastError(const ASourceType, ADestType: TVarType) |Raises an EVariantTypeCastError exception.
procedure VarCheckEmpty(const V: Variant) |Raises an exception if a specified variant’s value is Unassigned.
procedure VarClear(V: Variant) |Empties a Variant, so that it is unassigned.
function VarCompareValue(const A, B: Variant): TVariantRelationship |Returns the relationship between Variants.
function VarComplex: TVarType |Returns the Variant type code for custom Variants that represent complex numbers.
function VarComplexSimplify(const AValue: Variant): Variant |Reduces a Variant that represents a complex number to one that represents a real value, if possible.
function VarConvert: TVarType |Returns the Variant type code for custom Variants that represent measurements.
function VarConvertCreate(const AValue: string): Variant |Returns a custom Variant that represents a measurement.
function VarConvertCreate(const AValue: Double; const AType: TConvType): Variant |Returns a custom Variant that represents a measurement.
procedure VarCopyNoInd(var Dest: Variant; const Source: Variant) |Copies a Variant.
var VarDispProc: TVarDispProc |Provides the support for IDispatch-based Automation.
function VarEnsureRange(const AValue, AMin, AMax: Variant): Variant |Returns a Variant with a value in a specified range.

function VarFMTBcd: TVarType |Returns the TVarType constant that identifies the internal type of a Variant as a TBcd value.
procedure VarFMTBcdCreate(var aDest: Variant; const ABcd: TBcd) |Creates a new Variant that stores its value internally as a TBcd value.
function VarFMTBcdCreate(const ABcd: TBcd): Variant |Creates a new Variant that stores its value internally as a TBcd value.
function VarFMTBcdCreate(const AValue: string, Precision, Scale: Word): Variant |Creates a new Variant that stores its value internally as a TBcd value.
function VarFMTBcdCreate(const AValue: Double; Precision: Word = 18; Scale: Word = 4): Variant |Creates a new Variant that stores its value internally as a TBcd value.

function VarFromDateTime(DateTime: TDateTime): Variant |Returns a variant containing a specified data and time.
function VarInRange(const AValue, AMin, AMax: Variant): Boolean |Indicates whether a Variant’s value is in a specified range.
procedure VarInvalidNullOp |Indicate variant operation on null.
procedure VarInvalidOp |Indicate invalid variant operation.
function VarIsArray(const A: Variant[; AResolveByRef: Boolean]): Boolean |Indicates whether the specified variant is an array.
function VarIsByRef(const V: Variant): Boolean |Indicates whether the specified variant’s value is by reference.
function VarIsClear(const V: Variant): Boolean |Indicates whether the specified variant has an undefined value.
function VarIsComplex(const AValue: Variant): Boolean |Indicates whether a Variant stores its data internally as a complex number.
function VarIsConvert(const AValue: Variant): Boolean |Indicates whether a Variant is a custom Variant that represents a measurement.
function VarIsCustom(const AValue: Variant): Boolean |Indicates whether the specified variant is a custom variant.
function VarIsEmpty(const AValue: Variant): Boolean |Indicates whether the specified variant is unassigned.
function VarIsEmptyParam(const AValue: Variant): Boolean |Indicates whether the specified variant represents an unassigned optional parameter.
function VarIsError(const V: Variant[; out AResult: HRESULT]): Boolean |Indicates whether the specified variant is an error variant; optionally converts variant back to HRESULT.
function VarIsFloat(const V: Variant): Boolean |Indicates whether the specified variant represents a floating-point value.
function VarIsFMTBcd(const V: Variant): Boolean |Indicates whether a specified Variant represents a TBcd value.
function VarIsNull(const V: Variant): Boolean |Indicates whether the specified variant is Null.
function VarIsNumeric(const V: Variant): Boolean |Indicates whether the specified variant represents a numeric value.
function VarIsOrdinal(const V: Variant): Boolean |Indicates whether the specified variant represents an ordinal value.
function VarIsSQLTimeStamp(const V: Variant): Boolean |Indicates whether a specified Variant represents a TSQLTimeStamp value.
function VarIsStr(const V: Variant): Boolean |Indicates whether the specified variant represents a string value.
function VarIsType(const V: Variant; AVarType: TVarType): Boolean |Indicates whether the specified variant represents a specified type.
function VarIsType(const V: Variant; const AVarTypes: array of TVarType): Boolean |Indicates whether the specified variant represents a specified type.
procedure VarOverflowError(const ASourceType, ADestType: TVarType) |Raises an EVariantOverflowError exception.
procedure VarRangeCheckError(const ASourceType, ADestType: TVarType) |Raises an EVariantRangeCheckError exception.
procedure VarResultCheck(AResult: HRESULT) |Raises variant exception based on HRESULT value.
procedure VarResultCheck(AResult: HRESULT; ASourceType, ADestType: TVarType) |Raises variant exception based on HRESULT value.
function VarSameValue(const A, B: Variant): Boolean |Indicates whether two Variants have equivalent values.
function VarSQLTimeStamp: TVarType |Returns the TVarType constant that identifies the internal type of a Variant as a TSQLTimeStamp value.
procedure VarSQLTimeStampCreate(var aDest: Variant; const ASQLTimeStamp: TSQLTimeStamp) |Creates a new Variant that stores its value internally as a TSQLTimeStamp value.
function VarSQLTimeStampCreate(const ASQLTimeStamp: TSQLTimeStamp): Variant |Creates a new Variant that stores its value internally as a TSQLTimeStamp value.
function VarSQLTimeStampCreate(const AValue: TDateTime): Variant |Creates a new Variant that stores its value internally as a TSQLTimeStamp value.
function VarSQLTimeStampCreate(const AValue: string): Variant |Creates a new Variant that stores its value internally as a TSQLTimeStamp value.
function VarSupports(const V: Variant; const IID: TGUID[; out Intf]): Boolean |Indicates whether the Variant’s value is an interface that supports a specified interface.
function VarToBcd(const aValue: Variant): TBcd |Converts a Variant into a TBcd type.
function VarToDateTime(const V: Variant): TDateTime |Converts a specified variant to a TDateTime value.
function VarToSQLTimeStamp(const aValue: Variant): TSQLTimeStamp |Converts a Variant that represents a TSQLTimeStamp value to the corresponding TSQLTimeStamp.
function VarToStr(const V: Variant): string |Converts a variant's value to a string.
function VarToStrDef(const V: Variant; const ADefault: string): string |Converts a variant's value to a string.
function VarToWideStr(const V: Variant): WideString |Converts a variant's value to a WideString.
function VarToWideStrDef(const V: Variant; const ADefault: WideString): WideString |Converts a variant's value to a WideString.
function VarType(const V: Variant): TVarType |Returns the type code of a specified variant.
function VarTypeAsText(const AType: TVarType): string |Returns variant type descriptive string.
function VarTypeIsValidArrayType(const AVarType: TVarType): Boolean |Indicates whether a Variant type code represents a type that can be used for the elements in a Variant array.
function VarTypeIsValidElementType(const AVarType: TVarType): Boolean |Indicates whether a Variant type code represents a type that can be used for the elements in a Variant array.

var WakeMainThread: TNotifyEvent |Represents a method (event handler) that is forced into the main thread’s queue.

function WeekOf(const AValue: TDateTime): Word |Returns the week of the year represented by a TDateTime value.
function WeekOfTheMonth(const AValue: TDateTime[; var AYear, AMonth: Word]): Word |Returns the week of the month represented by a TDateTime value.
function WeekOfTheYear(const AValue: TDateTime[; var AYear: Word]): Word |Returns the week of the year represented by a TDateTime value.
function WeeksBetween(const ANow, AThen: TDateTime): Integer |Returns the number of whole weeks between two specified TDateTime values.
function WeeksInAYear(const AYear: Word): Word |Returns the number of weeks in a specified year.
function WeeksInYear(const AValue: TDateTime): Word |Returns the number of weeks in the year of a specified TDateTime value.
function WeekSpan(const ANow, AThen: TDateTime): Double |Returns the number of weeks (including fractional weeks) between two specified TDateTime values.

function WideCompareStr(const S1, S2: WideString): Integer |Compares Unicode strings based on the current locale with case sensitivity.
function WideCompareText(const S1, S2: WideString): Integer |Compares Unicode strings based on the current locale without case sensitivity.
procedure WideFmtStr(var Result: WideString; const Format: WideString; const Args: array of const[; const FormatSettings: TFormatSettings]) |Assembles a formatted Unicode string using a format string and an array of arguments.
function WideFormat(const Format: WideString; const Args: array of const[; const FormatSettings: TFormatSettings]): WideString |Returns a formatted Unicode string assembled from a format string and an array of arguments.
function WideFormatBuf(var Buffer; BufLen: Cardinal; const Format; FmtLen: Cardinal; const Args: array of const[; const FormatSettings: TFormatSettings]): Cardinal |Formats the arguments from an array, placing the result in a buffer.
function WideLowerCase(const S: WideString): WideString |Returns Unicode string converted to lower case.
function WideSameCaption(const Text1, Text2: WideString): Boolean |Indicates whether two strings are the same based on the current Windows locale, ignoring case information and accelerator characters.
function WideSameStr(const S1, S2: WideString): Boolean |Compares Unicode strings based on the current locale with case sensitivity.
function WideSameText(const S1, S2: WideString): Boolean |Compares Unicode strings based on the current locale without case sensitivity.
function WideUpperCase(const S: WideString): WideString |Returns Unicode string converted to upper case.

function Win32Check(RetVal: BOOL): BOOL |Checks the return value of a Windows API call and raises an appropriate exception when it indicates failure.

function WithinPastDays(const ANow, AThen: TDateTime; const ADays: Integer): Boolean |Indicates whether two dates are within a specified number of days of each other.
function WithinPastHours(const ANow, AThen: TDateTime; const AHours: Int64): Boolean |Indicates whether two date/time values are within a specified number of hours of each other.
function WithinPastMilliSeconds(const ANow, AThen: TDateTime; const AMilliSeconds: Int64): Boolean |Indicates whether two date/time values are within a specified number of milliseconds of each other.
function WithinPastMinutes(const ANow, AThen: TDateTime; const AMinutes: Int64): Boolean |Indicates whether two date/time values are within a specified number of minutes of each other.
function WithinPastMonths(const ANow, AThen: TDateTime; const AMonths: Integer): Boolean |Indicates whether two date/time values are within a specified number of months of each other.
function WithinPastSeconds(const ANow, AThen: TDateTime; const ASeconds: Int64): Boolean |Indicates whether two date/time values are within a specified number of seconds of each other.
function WithinPastWeeks(const ANow, AThen: TDateTime; const AWeeks: Integer): Boolean |Indicates whether two date/time values are within a specified number of weeks of each other.
function WithinPastYears(const ANow, AThen: TDateTime; const AYears: Integer): Boolean |Indicates whether two date/time values are within a specified number of years of each other.

function WrapText(const Line, BreakStr: string; nBreakChars: TSysCharSet; MaxCol: Integer): string |Returns a string broken into multiple lines.
procedure Write(F, V1,...,Vn) |Writes to a typed file.
procedure WriteComponentResFile(const FileName: string; Instance: TComponent) |Writes components and their properties to a file using a resource file format.
procedure WriteLn([var F: Text;] P1 [, P2, ...,Pn]) |Writes to a text file and adds an end-of-line marker.

function YearOf(const AValue: TDateTime): Word |Returns the year represented by a TDateTime value.
function YearsBetween(const ANow, AThen: TDateTime): Integer |Gives the number of whole years between two specified dates.
function YearSpan(const ANow, AThen: TDateTime): Double |Returns the approximate number of years between two TDateTime values.
function Yesterday: TDateTime |Returns a TDateTime value that represents the preceding day.

var Application: TApplication |Represents application-level information.
var CmdLine: PChar |Returns the pointer to string that contains the command-line arguments.
var CmdShow: Integer |Specifies the flags for displaying the application's main window.
const CompilerVersion |Designates the version number of the Delphi compiler.
var ExitProc: Pointer |Points to a program's exit procedure (provided for backward compatibility).
var ExitProcessProc: procedure |Specifies the last procedure to execute before the application shuts down.
var HInstance: LongWord |Indicates the handle for a module.
var HintWindowClass: THintWindowClass |Specifies the class for the window used to display help hints.
var InitProc: Pointer |InitProc is the last installed initialization procedure.
var IsConsole: Boolean |Indicates whether the module was compiled as a console application.
var IsLibrary: Boolean |Indicates whether the module is a shared library.
var JITEnable: Byte |Controls when the just-in-time debugger is called.
function Languages: TLanguages |Lists the locales for which support is available.
var MainInstance: LongWord |Indicates the instance handle for the main executable.
var MainThreadID: LongWord |Indicates the instance handle for the current module's main thread of execution.
var NoErrMsg: Boolean |Controls whether the application displays an error message when a runtime error occurs.
var PopupList: TPopupList |Provides centralized handling of Windows messages directed at popup menus.
const RTLVersion |Designates the version number of the Delphi runtime library.
var Screen: TScreen |Represents the screen device.
var Win32Platform: Integer |Specifies the Win32 platform identifier.

var CurrencyString: string |Defines the currency symbol (or characters) used in floating-point to decimal conversions.
var CurrencyFormat: Byte |Defines the currency symbol placement and separation used in floating-point–to–decimal conversions.
var NegCurrFormat: Byte |Defines the currency format used in floating-point to decimal conversions of negative numbers.
var ThousandSeparator: Char |The character used to separate thousands in numbers with more than three digits to the left of the decimal separator.
var DecimalSeparator: Char |The character used to separate the integer part from the fractional part of a number.
var CurrencyDecimals: Byte |The number of digits to the right of the decimal point in a currency amount.
var DateSeparator: Char |The character used to separate the year, month, and day parts of a date value.
var ShortDateFormat: string |The format string used to convert a date value to a short string suitable for editing.
var LongDateFormat: string |The format string used to convert a date value to a long string suitable for display but not for editing.
var TimeSeparator: Char |The character used to separate the hour, minute, and second parts of a time value.
var TimeAMString: string |The suffix string used for time values between 00:00 and 11:59 in 12-hour clock format.
var TimePMString: string |The suffix string used for time values between 12:00 and 23:59 in 12-hour clock format.
var ShortTimeFormat: string |The format string used to convert a time value to a short string with only hours and minutes.
var LongTimeFormat: string |The format string used to convert a time value to a string with hours, minutes, and seconds.
var ShortMonthNames: array[1..12] of string |The array of strings containing short month names.
var LongMonthNames: array[1..12] of string |The array of strings containing long month names.
var ShortDayNames: array[1..7] of string |The array of strings containing short day names.
var LongDayNames: array[1..7] of string |The array of strings containing long day names.
var SysLocale: TSysLocale |Indicates the locale used by FormatDateTime to interpret dates.
var EraNames: array[1..7] of string |Controls the DateTimeToStr function (for East Asian locales).
var EraYearOffsets: array[1..7] of Integer |Controls the DateTimeToStr function (for East Asian locales).
var TwoDigitYearCenturyWindow: Word |Determines what century is added to two-digit years when string dates are converted to numeric dates.
var ListSeparator: Char |The character used to separate items in a list.

const fmClosed |closed file
const fmInput |reset file (TTextRec)
const fmOutput |rewritten file (TTextRec)
const fmInOut |reset or rewritten file (TFileRec)
const fmCRLF |DOS-style EoL and EoF markers (TTextRec)
const fmMask |mask out fmCRLF flag (TTextRec)

const fmCreate |If the file exists, open for write access, otherwise, create a new file.
const fmOpenRead |Open for read access only.
const fmOpenWrite |Open for write access only.
const fmOpenReadWrite |Open for read and write access.
const fmShareCompat |Compatible with the way FCBs are opened. Do not use this mode in cross-platform applications.
const fmShareExclusive |Read and write access is denied.
const fmShareDenyWrite |Write access is denied.
const fmShareDenyRead |Read access is denied. Do not use this mode in cross-platform applications.
const fmShareDenyNone |Allows full access for others.

const DayMonday |1
const DayTuesday |2
const DayWednesday |3
const DayThursday |4
const DayFriday |5
const DaySaturday |6
const DaySunday |7

type TFPUException |(exInvalidOp, exDenormalized, exZeroDivide, exOverflow, exUnderflow, exPrecision)
type TFPUExceptionMask |set of TFPUException
type TFPUPrecisionMode |(pmSingle, pmReserved, pmDouble, pmExtended)
type TFPURoundingMode |(rmNearest, rmDown, rmUp, rmTruncate)

const HoursPerDay |24
const MinsPerHour |60
const SecsPerMin |60
const MSecsPerSec |1000
const MinsPerDay |HoursPerDay * MinsPerHour
const SecsPerDay |MinsPerDay * SecsPerMin
const MSecsPerDay |SecsPerDay * MSecsPerSec

