[antlr-interest] Grammar handling of whitespaces

[Johannes Luber]

Shawn Poulson schrieb:
> Hello all,
> 
> I've had success so far with generating my grammar for my C# target,
> with help from several individuals here.  One of the tips I've used is
> to use a lexer rule to skip whitespaces using a rule like:
> 
> WS : (' '|'\r'|'\t'|'\n') { $channel=HIDDEN; }
> 
> This is very helpful for most parser rules, so I don't have to
> explicitly put whitespaces throughout my parser rules.  But, there are
> times where I don't want whitespaces between certain elements.  Is
> there a way to handle this?

Untested yet, but this should work:

arrow
	:	first=ASSIGNMENT second=GT {$first.index + 1 == $second.index}? // 
Nothing between the tokens?
	;

Johannes