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[haberg]

@nostromo.lrde.epita.fr>
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From: Hans Aberg <address@hidden>
Subject: Re: %type {...} a b c
Date: Wed, 12 Jul 2006 21:35:46 +0200
To: Akim Demaille <address@hidden>
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On 12 Jul 2006, at 17:51, Akim Demaille wrote:

>>>> "Joel" == Joel E Denny <address@hidden> writes:
>
>> I like the idea of equating a semantic type with a type in the
>> target language rather than with a union field name.  I also see
>> how modules might conflict on a field name, but types don't have
>> that problem.
>
> It also solves one of the issues to support C++ variants in bison,
> where we do not rely on a union, but on a templated structure,
> parametrized by the various types.  That's *if* we use Boost Variants.

Those seem OK for the specialty programmer, though not for general  
use. :-) But when static typing is used, one will hit the problem  
with the implementation of default rules, which will be $<type>$ =  
$<type>1 instead of the current untyped $$ = $1.

   Hans Aberg