[antlr-interest] Syntax confirmation

[Kay Roepke]

Hi Phil!

On 4. Aug 2006, at 12:46 Uhr, Phil Ritchie wrote:

> Am I correct in my understanding:
>
> [snippet from grammar file]
> file
>     : rec=record -> {%file(r={$rec.text})}
>     ;
>
> %file corresponds to a StringTemplate template.
> r corresponds to the template parameter

Sort of, yes.
The '->' is already a rewrite operation. So the rule must be:
file
	: rec=record -> file(r={$rec.text})
	;

This would indeed use the template you mentioned.
The % notation is for use in actions that are not part of rewrites,  
when you need to instantiate templates yourself:

file
	: rec=record {StringTemplate recTmpl = %file(r={$rec.text});}
	;

This amounts to the same thing, only it is not automatically set in  
the rule's return value.

See the cminus example in the examples <http://www.antlr.org/download/ 
examples-v3.tar.gz> for a lot of template instantiations :)
Or for a real life example look at Ter's Mantra language (<http:// 
linguamantra.org/>).

HTH,

-k

-- 
Kay Röpke <kroepke at classdump.org>
classdump Software