[antlr-interest] java.g - a couple of issues

[Jon Schewe]

One problem with this is that if you remove the calls to newline(),
you're line numbers will be off.  This makes error reporting rather
difficult.

On Fri, 2005-03-18 at 12:24 +1100, Davin McCall wrote:
> To clarify, we have changed the single line comment target "SL_COMMENT" 
> as follows:
> 
> (Original)
> // Single-line comments
> SL_COMMENT
>     :    "//"
>         (~('\n'|'\r'))* ('\n'|'\r'('\n')?)
>         {$setType(Token.SKIP); newline();}
>     ;
> 
> (Modified)
> // Single-line comments
> SL_COMMENT
>     :    "//"
>         (~('\n'|'\r'))*
>         {$setType(Token.SKIP); }
>     ;
> 
> And the typeArgumentBounds target from:
> 
> typeArgumentBounds[boolean addImagNode]
>     {boolean isUpperBounds = false;}
>     :
>         ( "extends"! {isUpperBounds=true;} | "super"! ) 
> classOrInterfaceType[addImagNode]
>         {
>             if (isUpperBounds)
>             {
>                 #typeArgumentBounds = 
> #(#[TYPE_UPPER_BOUNDS,"TYPE_UPPER_BOUNDS"], #typeArgumentBounds);
>             }
>             else
>             {
>                 #typeArgumentBounds = 
> #(#[TYPE_LOWER_BOUNDS,"TYPE_LOWER_BOUNDS"], #typeArgumentBounds);
>             }
>         }
>     ;
> 
> To:
> 
> typeArgumentBounds[boolean addImagNode]
>     {boolean isUpperBounds = false;}
>     :
>         ( "extends"! {isUpperBounds=true;} | "super"! ) 
> classOrInterfaceType[addImagNode] arraySpecOpt
>         {
>             if (isUpperBounds)
>             {
>                 #typeArgumentBounds = 
> #(#[TYPE_UPPER_BOUNDS,"TYPE_UPPER_BOUNDS"], #typeArgumentBounds);
>             }
>             else
>             {
>                 #typeArgumentBounds = 
> #(#[TYPE_LOWER_BOUNDS,"TYPE_LOWER_BOUNDS"], #typeArgumentBounds);
>             }
>         }
>     ;
> 
> 
> Davin
> 
> 
> Davin McCall wrote:
> 
> > Hi,
> > We're using Michael Studman's java 1.5 grammar as a base for our own 
> > and have noticed the following issues. We've got fixes but I wanted to 
> > both highlight the issues to the community and see if anyone else has 
> > comments (especially in regards to whether the fixes are correct :-) ).
> >
> > 1. Single line comments without a terminating newline at the end of a 
> > file cause a parse error, due to the requirement that the comment is 
> > followed by a line-end.
> >
> > It seems to be possible to just remove that requirement (and also the 
> > call to newline()) and then everything works fine (ie. the match is 
> > greedy anyway).
> >
> > 2. Arrays aren't allowed as wildcard bounds (they should be).
> >
> > For instance, "? extends Thread[]" as a wildcard in some declaration 
> > causes a parse error. A possible fix is to add "arraySpecOpt" in to 
> > the "typeArgumentBounds" target.
> >
> > Davin
> >
> >
> >

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