@nostromo.lrde.epita.fr> Mime-Version: 1.0 (Apple Message framework v752.2) Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Message-Id: <[EMAIL PROTECTED]> Cc: "Joel E. Denny" <[EMAIL PROTECTED]>, Paul Eggert <[EMAIL PROTECTED]>, [email protected] Content-Transfer-Encoding: 7bit From: Hans Aberg <[EMAIL PROTECTED]> Subject: Re: %type {...} a b c Date: Wed, 12 Jul 2006 21:35:46 +0200 To: Akim Demaille <[EMAIL PROTECTED]> X-Mailer: Apple Mail (2.752.2)
On 12 Jul 2006, at 17:51, Akim Demaille wrote: >>>> "Joel" == Joel E Denny <[EMAIL PROTECTED]> 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
