[antlr-interest] Grammar Problem

[Bogdan Mitu]

Hi,

Why rule startHTMLTag starts with INITSTARTTAG, while the others not? 
It seems that you use embedded lexer and parser for HTML tags. You probably
have in the main lexer a rule that recognize '<' and switches the lexer. The
Tag Parser is connected to the second lexer, and will never receive the
INITSTARTTAG token it is expecting in the rule startHTMLTag.

Try:
startHTMLTag : /* INITSTARTTAG removed */ tagName:TAGDATA
                {System.out.println("STARTTAG : "+tagName.getText());}
                FINISHSTARTTAG;
 
Bogdan


--- johnclarke72 <johnclarke at hotmail.com> wrote:
> Hi,
>    I am currently having problems with a HTML Grammar that I am 
> writing.  The Grammar has been added to the end of this e-mail.
> 
> When I enter HTML comments (<!-- This is a Comment -->) and End Tags 
> (</endTag>) it handles it correctly.
> 
> However,  if I enter <test> or anything similar to this I get 
> an "line 1: unexpected token: test" error message.  
> 
> How can I get this to work ?
> 
> I would be grateful for all advice offered regarding this.
> 
> John
> 
> HTMLTagLexer.g
> ==============
> 
> // Import the required Classes
> header
> {
>    import java.util.*;
>    import antlr.*;
> }
> 
> // Define the class
> class HTMLTagLexer extends Lexer;
> 
> // Set the options for the Lexer
> options
> {
>   k=3;                             // Set the look ahead to 3 
> Characters
>   caseSensitive = false;           // Set Case Sensitivity to false
>   charVocabulary = '\1' .. '\377'; // Set the Lexer Character 
> Vocabulary
>   testLiterals = false;            // Don't test against the Literals 
> table
>   exportVocab = HTMLTagLexer;      // The Grammar to export
> }
> 
> // The routines that will enable us to switch between lexer states
> {
>    // The Current Selector
>    TokenStreamSelector selector;
> 
>    // The method that will enable us to switch between lexer states
>    public void setSelector(TokenStreamSelector tokenStreamSelector)
>    {
>      selector = tokenStreamSelector;
>    }
> }
> 
> // Define the Tokens required for the Grammar
> 
> // Various HTML Marker Tags
> INITSTARTTAG   : "<";
> FINISHSTARTTAG : ">";
> EQUALS         : "=";
> 
> // HTML Comments
> HTMLCOMMENT : "!--"! (options {greedy=false;} : .)* "-->"!
>               {selector.pop();}
>               ;
> 
> // Main HTML Tags Section.  This defines the Tag names,
> // attributes and attribute values
> 
> // TAGDATA is used to define the Tag Name and names of
> // attributes used within the tag
> TAGDATA : (~(' ' | '\r' | '\n' | '\t' | '<' | '>' | '/' | '!' | '='))
> +;
> 
> // TAGVALUE is used to define the values for attributes
> // used within the tags
> 
> 
> // Definition of an End Tag
> ENDTAG   : '/'! ( 'a'..'z' )+ ">"! {selector.pop();};
> 
> // Ignore all White Space
> WS : ( ' '
>      | '\t'
>      | '\r' '\n' { newline(); }
>      | '\n' { newline(); }
>      )
>      {$setType(Token.SKIP);} //ignore this token
> ;
> 
> HTMLTagParser.g
> ===============
> 
> // Define the class
> class HTMLTagParser extends Parser;
> 
> // Set the options for the Parser
> options
> {
>   importVocab = HTMLTagLexer;     // The Grammar to import
> }
> 
> 
> // The Parser Rules
> processHTML:
>    htmlComment:HTMLCOMMENT {System.out.println
> ("COMMENT : "+htmlComment.getText().trim());}
>    | startHTMLTag
>    | endTag:ENDTAG {System.out.println("ENDTAG : "+endTag.getText
> ());};
> 
> startHTMLTag : INITSTARTTAG tagName:TAGDATA
>                {System.out.println("STARTTAG : "+tagName.getText());}
>                FINISHSTARTTAG;
> 
> 
> 
> 
>  
> 
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ 
> 
> 
> 


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