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Diffstat (limited to 'runtime/CSharp3/Sources/Antlr3.Runtime/Lexer.cs')
| -rw-r--r-- | runtime/CSharp3/Sources/Antlr3.Runtime/Lexer.cs | 443 |
1 files changed, 0 insertions, 443 deletions
diff --git a/runtime/CSharp3/Sources/Antlr3.Runtime/Lexer.cs b/runtime/CSharp3/Sources/Antlr3.Runtime/Lexer.cs deleted file mode 100644 index daf530d..0000000 --- a/runtime/CSharp3/Sources/Antlr3.Runtime/Lexer.cs +++ /dev/null @@ -1,443 +0,0 @@ -/* - * [The "BSD licence"] - * Copyright (c) 2005-2008 Terence Parr - * All rights reserved. - * - * Conversion to C#: - * Copyright (c) 2008-2009 Sam Harwell, Pixel Mine, Inc. - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. The name of the author may not be used to endorse or promote products - * derived from this software without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR - * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES - * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. - * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, - * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT - * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, - * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY - * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF - * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - */ - -namespace Antlr.Runtime -{ - using ConditionalAttribute = System.Diagnostics.ConditionalAttribute; - - /** <summary> - * A lexer is recognizer that draws input symbols from a character stream. - * lexer grammars result in a subclass of this object. A Lexer object - * uses simplified match() and error recovery mechanisms in the interest - * of speed. - * </summary> - */ - public abstract class Lexer : BaseRecognizer, ITokenSource - { - /** <summary>Where is the lexer drawing characters from?</summary> */ - protected ICharStream input; - - public Lexer() - { - } - - public Lexer( ICharStream input ) - { - this.input = input; - } - - public Lexer( ICharStream input, RecognizerSharedState state ) - : base(state) - { - this.input = input; - } - - #region Properties - public string Text - { - /** <summary>Return the text matched so far for the current token or any text override.</summary> */ - get - { - if ( state.text != null ) - { - return state.text; - } - return input.Substring( state.tokenStartCharIndex, CharIndex - state.tokenStartCharIndex ); - } - /** <summary>Set the complete text of this token; it wipes any previous changes to the text.</summary> */ - set - { - state.text = value; - } - } - public int Line - { - get - { - return input.Line; - } - set - { - input.Line = value; - } - } - public int CharPositionInLine - { - get - { - return input.CharPositionInLine; - } - set - { - input.CharPositionInLine = value; - } - } - #endregion - - public override void Reset() - { - base.Reset(); // reset all recognizer state variables - // wack Lexer state variables - if ( input != null ) - { - input.Seek( 0 ); // rewind the input - } - if ( state == null ) - { - return; // no shared state work to do - } - state.token = null; - state.type = TokenTypes.Invalid; - state.channel = TokenChannels.Default; - state.tokenStartCharIndex = -1; - state.tokenStartCharPositionInLine = -1; - state.tokenStartLine = -1; - state.text = null; - } - - /** <summary>Return a token from this source; i.e., match a token on the char stream.</summary> */ - public virtual IToken NextToken() - { - for ( ; ; ) - { - state.token = null; - state.channel = TokenChannels.Default; - state.tokenStartCharIndex = input.Index; - state.tokenStartCharPositionInLine = input.CharPositionInLine; - state.tokenStartLine = input.Line; - state.text = null; - if ( input.LA( 1 ) == CharStreamConstants.EndOfFile ) - { - return GetEndOfFileToken(); - } - try - { - ParseNextToken(); - if ( state.token == null ) - { - Emit(); - } - else if ( state.token == Tokens.Skip ) - { - continue; - } - return state.token; - } - catch (MismatchedRangeException mre) - { - ReportError(mre); - // MatchRange() routine has already called recover() - } - catch (MismatchedTokenException mte) - { - ReportError(mte); - // Match() routine has already called recover() - } - catch ( RecognitionException re ) - { - ReportError( re ); - Recover( re ); // throw out current char and try again - } - } - } - - /** Returns the EOF token (default), if you need - * to return a custom token instead override this method. - */ - public virtual IToken GetEndOfFileToken() - { - IToken eof = new CommonToken((ICharStream)input, CharStreamConstants.EndOfFile, TokenChannels.Default, input.Index, input.Index); - eof.Line = Line; - eof.CharPositionInLine = CharPositionInLine; - return eof; - } - - /** <summary> - * Instruct the lexer to skip creating a token for current lexer rule - * and look for another token. nextToken() knows to keep looking when - * a lexer rule finishes with token set to SKIP_TOKEN. Recall that - * if token==null at end of any token rule, it creates one for you - * and emits it. - * </summary> - */ - public virtual void Skip() - { - state.token = Tokens.Skip; - } - - /** <summary>This is the lexer entry point that sets instance var 'token'</summary> */ - public abstract void mTokens(); - - public virtual ICharStream CharStream - { - get - { - return input; - } - /** <summary>Set the char stream and reset the lexer</summary> */ - set - { - input = null; - Reset(); - input = value; - } - } - - public override string SourceName - { - get - { - return input.SourceName; - } - } - - /** <summary> - * Currently does not support multiple emits per nextToken invocation - * for efficiency reasons. Subclass and override this method and - * nextToken (to push tokens into a list and pull from that list rather - * than a single variable as this implementation does). - * </summary> - */ - public virtual void Emit( IToken token ) - { - state.token = token; - } - - /** <summary> - * The standard method called to automatically emit a token at the - * outermost lexical rule. The token object should point into the - * char buffer start..stop. If there is a text override in 'text', - * use that to set the token's text. Override this method to emit - * custom Token objects. - * </summary> - * - * <remarks> - * If you are building trees, then you should also override - * Parser or TreeParser.getMissingSymbol(). - * </remarks> - */ - public virtual IToken Emit() - { - IToken t = new CommonToken( input, state.type, state.channel, state.tokenStartCharIndex, CharIndex - 1 ); - t.Line = state.tokenStartLine; - t.Text = state.text; - t.CharPositionInLine = state.tokenStartCharPositionInLine; - Emit( t ); - return t; - } - - public virtual void Match( string s ) - { - int i = 0; - while ( i < s.Length ) - { - if ( input.LA( 1 ) != s[i] ) - { - if ( state.backtracking > 0 ) - { - state.failed = true; - return; - } - MismatchedTokenException mte = new MismatchedTokenException(s[i], input, TokenNames); - Recover( mte ); - throw mte; - } - i++; - input.Consume(); - state.failed = false; - } - } - - public virtual void MatchAny() - { - input.Consume(); - } - - public virtual void Match( int c ) - { - if ( input.LA( 1 ) != c ) - { - if ( state.backtracking > 0 ) - { - state.failed = true; - return; - } - MismatchedTokenException mte = new MismatchedTokenException(c, input, TokenNames); - Recover( mte ); // don't really recover; just consume in lexer - throw mte; - } - input.Consume(); - state.failed = false; - } - - public virtual void MatchRange( int a, int b ) - { - if ( input.LA( 1 ) < a || input.LA( 1 ) > b ) - { - if ( state.backtracking > 0 ) - { - state.failed = true; - return; - } - MismatchedRangeException mre = new MismatchedRangeException(a, b, input); - Recover( mre ); - throw mre; - } - input.Consume(); - state.failed = false; - } - - /** <summary>What is the index of the current character of lookahead?</summary> */ - public virtual int CharIndex - { - get - { - return input.Index; - } - } - - public override void ReportError( RecognitionException e ) - { - /** TODO: not thought about recovery in lexer yet. - * - // if we've already reported an error and have not matched a token - // yet successfully, don't report any errors. - if ( errorRecovery ) { - //System.err.print("[SPURIOUS] "); - return; - } - errorRecovery = true; - */ - - DisplayRecognitionError( this.TokenNames, e ); - } - - public override string GetErrorMessage( RecognitionException e, string[] tokenNames ) - { - string msg = null; - if ( e is MismatchedTokenException ) - { - MismatchedTokenException mte = (MismatchedTokenException)e; - msg = "mismatched character " + GetCharErrorDisplay( e.Character ) + " expecting " + GetCharErrorDisplay( mte.Expecting ); - } - else if ( e is NoViableAltException ) - { - NoViableAltException nvae = (NoViableAltException)e; - // for development, can add "decision=<<"+nvae.grammarDecisionDescription+">>" - // and "(decision="+nvae.decisionNumber+") and - // "state "+nvae.stateNumber - msg = "no viable alternative at character " + GetCharErrorDisplay( e.Character ); - } - else if ( e is EarlyExitException ) - { - EarlyExitException eee = (EarlyExitException)e; - // for development, can add "(decision="+eee.decisionNumber+")" - msg = "required (...)+ loop did not match anything at character " + GetCharErrorDisplay( e.Character ); - } - else if ( e is MismatchedNotSetException ) - { - MismatchedNotSetException mse = (MismatchedNotSetException)e; - msg = "mismatched character " + GetCharErrorDisplay( e.Character ) + " expecting set " + mse.Expecting; - } - else if ( e is MismatchedSetException ) - { - MismatchedSetException mse = (MismatchedSetException)e; - msg = "mismatched character " + GetCharErrorDisplay( e.Character ) + " expecting set " + mse.Expecting; - } - else if ( e is MismatchedRangeException ) - { - MismatchedRangeException mre = (MismatchedRangeException)e; - msg = "mismatched character " + GetCharErrorDisplay( e.Character ) + " expecting set " + - GetCharErrorDisplay( mre.A ) + ".." + GetCharErrorDisplay( mre.B ); - } - else - { - msg = base.GetErrorMessage( e, tokenNames ); - } - return msg; - } - - public virtual string GetCharErrorDisplay( int c ) - { - string s = ( (char)c ).ToString(); - switch ( c ) - { - case TokenTypes.EndOfFile: - s = "<EOF>"; - break; - case '\n': - s = "\\n"; - break; - case '\t': - s = "\\t"; - break; - case '\r': - s = "\\r"; - break; - } - return "'" + s + "'"; - } - - /** <summary> - * Lexers can normally match any char in it's vocabulary after matching - * a token, so do the easy thing and just kill a character and hope - * it all works out. You can instead use the rule invocation stack - * to do sophisticated error recovery if you are in a fragment rule. - * </summary> - */ - public virtual void Recover( RecognitionException re ) - { - //System.out.println("consuming char "+(char)input.LA(1)+" during recovery"); - //re.printStackTrace(); - input.Consume(); - } - - [Conditional("ANTLR_TRACE")] - public virtual void TraceIn( string ruleName, int ruleIndex ) - { - string inputSymbol = ( (char)input.LT( 1 ) ) + " line=" + Line + ":" + CharPositionInLine; - base.TraceIn( ruleName, ruleIndex, inputSymbol ); - } - - [Conditional("ANTLR_TRACE")] - public virtual void TraceOut( string ruleName, int ruleIndex ) - { - string inputSymbol = ( (char)input.LT( 1 ) ) + " line=" + Line + ":" + CharPositionInLine; - base.TraceOut( ruleName, ruleIndex, inputSymbol ); - } - - protected virtual void ParseNextToken() - { - mTokens(); - } - } -} |