Remarks

Lexer for EC# source code (see ILexer<Token>).

See also: TokensToTree

Public fields
bool	AllowNestedComments = false

int	SpacesPerTab = 4

Properties
new ISourceFile	SourceFile `[get]`

int	IndentLevel `[get]`

UString	IndentString `[get]`

Properties inherited from Loyc.Syntax.Lexing.BaseLexer< CharSrc >
IMessageSink??	ErrorSink `[get, set]`
	Gets or sets the object to which error messages are sent. The default object is LogExceptionErrorSink, which throws an exception if an error occurs. More...

int	LA0 `[get]`

CharSrc	CharSource `[get]`

string	FileName `[get]`

int	InputPosition `[get, protected set]`

LexerSourceFile< CharSrc >	SourceFile `[get]`

int	LineNumber `[get]`
	Current line number. Starts at 1 for the first line, unless derived class changes it. More...

int	LineStartAt `[get]`
	Index at which the current line started. More...

Properties inherited from Loyc.Syntax.IHasFileName
string	FileName `[get]`

Properties inherited from Loyc.Syntax.Lexing.ILexer< Token >
ISourceFile	SourceFile `[get]`
	The file being lexed. More...

IMessageSink	ErrorSink `[get, set]`
	Event handler for errors. More...

int	IndentLevel `[get]`
	Indentation level of the current line. This is updated after scanning the first whitespaces on a new line, and may be reset to zero when NextToken() returns a newline. More...

UString	IndentString `[get]`
	Gets a string slice that holds the spaces or tabs that were used to indent the current line. More...

int	LineNumber `[get]`
	Current line number (1 for the first line). More...

int	InputPosition `[get]`
	Current input position (an index into SourceFile.Text). More...

Public Member Functions
	EcsLexer (string text, IMessageSink sink)

	EcsLexer (ICharSource text, string fileName, IMessageSink sink, int startPosition=0)

void	Reset (ICharSource source, string fileName="", int inputPosition=0)

Maybe< Token >	NextToken ()
	Scans the next token and returns information about it. More...

void	Restart ()

Public Member Functions inherited from Loyc.Syntax.Lexing.BaseLexer< CharSrc >
	BaseLexer (CharSrc chars, string fileName="", int inputPosition=0, bool newSourceFile=true)
	Initializes BaseLexer. More...

virtual void	Reset (CharSrc chars, string fileName="", int inputPosition=0, bool newSourceFile=true)
	Reinitializes the object. This method is called by the constructor. More...

LineColumnFile	IndexToLine (int charIndex)
	Returns the position in a source file of the specified index. More...

Static Public Member Functions
static int	MeasureIndent (UString indent, int spacesPerTab)

Protected Member Functions
override void	Error (int lookaheadIndex, string message)
	This method is called to handle errors that occur during lexing. More...

new int	LA (int i)

Protected Member Functions inherited from Loyc.Syntax.Lexing.BaseLexer< CharSrc >
void	Reset ()

int	LA (int i)

void	Skip ()
	Increments InputPosition. Called by LLLPG when prediction already verified the input (and caller doesn't save LA(0)) More...

virtual void	AfterNewline ()
	The lexer must call this method exactly once after it advances past each newline, even inside comments and strings. This method keeps the LineNumber and LineStartAt properties updated. More...

	BaseLexer (ICharSource source, string fileName="", int inputPosition=0, bool newSourceFile=true)

void	Newline ()
	Default newline parser that matches ' ' or '\r' unconditionally. More...

void	Spaces ()
	Skips past any spaces at the current position. Equivalent to `rule Spaces @[ (' '\|'\t')* ]` in LLLPG. More...

int	MatchAny ()

int	Match (HashSet< int > set)

int	Match (int a)

int	Match (int a, int b)

int	Match (int a, int b, int c)

int	Match (int a, int b, int c, int d)

int	MatchRange (int aLo, int aHi)

int	MatchRange (int aLo, int aHi, int bLo, int bHi)

int	MatchExcept ()

int	MatchExcept (HashSet< int > set)

int	MatchExcept (int a)

int	MatchExcept (int a, int b)

int	MatchExcept (int a, int b, int c)

int	MatchExcept (int a, int b, int c, int d)

int	MatchExceptRange (int aLo, int aHi)

int	MatchExceptRange (int aLo, int aHi, int bLo, int bHi)

bool	TryMatch (HashSet< int > set)

bool	TryMatch (int a)

bool	TryMatch (int a, int b)

bool	TryMatch (int a, int b, int c)

bool	TryMatch (int a, int b, int c, int d)

bool	TryMatchRange (int aLo, int aHi)

bool	TryMatchRange (int aLo, int aHi, int bLo, int bHi)

bool	TryMatchExcept ()

bool	TryMatchExcept (HashSet< int > set)

bool	TryMatchExcept (int a)

bool	TryMatchExcept (int a, int b)

bool	TryMatchExcept (int a, int b, int c)

bool	TryMatchExcept (int a, int b, int c, int d)

bool	TryMatchExceptRange (int aLo, int aHi)

bool	TryMatchExceptRange (int aLo, int aHi, int bLo, int bHi)

virtual void	Check (bool expectation, string expectedDescr="")

virtual void	Error (int lookaheadIndex, string format, params object[] args)
	This method is called to format and handle errors that occur during lexing. The default implementation sends errors to ErrorSink, which, by default, throws a FormatException. More...

virtual object	IndexToPositionObject (int charIndex)

virtual void	MatchError (bool inverted, params int[] ranges)

virtual void	MatchError (bool inverted, IList< int > ranges)
	Handles an error that occurs during Match(), MatchExcept(), MatchRange() or MatchExceptRange() More...

virtual void	Error (bool inverted, HashSet< int > set)

string	RangesToString (IList< int > ranges)
	Converts a list of character ranges to a string, e.g. for input list {'','','a','z'}, the output is "'*' 'a'..'z'". More...

void	PrintChar (int c, StringBuilder sb)
	Prints a character as a string, e.g. `'a' -> "'a'"`, with the special value -1 representing EOF, so PrintChar(-1, ...) == "EOF". More...

Protected fields
Dictionary< UString, object >	_idCache = new Dictionary<UString, object>()

Protected fields inherited from Loyc.Syntax.Lexing.BaseLexer< CharSrc >
int	CachedBlockSize = 512

int	_lineStartAt

int	_lineNumber = 1

Additional Inherited Members
Public static fields inherited from Loyc.Syntax.Lexing.BaseLexer< CharSrc >
static readonly IMessageSink	LogExceptionErrorSink
	Throws LogException when it receives an error. Non-errors are sent to MessageSink.Default. More...

static readonly IMessageSink	FormatExceptionErrorSink

Static Protected Member Functions inherited from Loyc.Syntax.Lexing.BaseLexer< CharSrc >
static HashSet< int >	NewSet (params int[] items)

static HashSet< int >	NewSetOfRanges (params int[] ranges)

Member Function Documentation

◆ Error()

override void Loyc.Ecs.Parser.EcsLexer.Error	(	int	lookaheadIndex,
		string	message
	)

inlineprotectedvirtual

This method is called to handle errors that occur during lexing.

Parameters

lookaheadIndex	Index where the error occurred, relative to the current InputPosition (i.e. InputPosition + lookaheadIndex is the position of the error).
message	An error message, not including the error location.

Reimplemented from Loyc.Syntax.Lexing.BaseLexer< CharSrc >.

References Loyc.Syntax.Lexing.BaseLexer< CharSrc >.ErrorSink.