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From: Hans Aberg <haberg-1@telia.com>
To: Andy Wingo <wingo@pobox.com>
Cc: guile-devel <guile-devel@gnu.org>
Subject: Re: Avoiding variable clashes
Date: Wed, 13 Apr 2011 17:46:46 +0200	[thread overview]
Message-ID: <B877DFED-6391-4AB1-96DD-5BDA7253FDD6@telia.com> (raw)
In-Reply-To: <m339lmgoi6.fsf@unquote.localdomain>

On 13 Apr 2011, at 17:27, Andy Wingo wrote:

>>>> What method is Guile using to avoid substitution variable clashes (de
>>>> Bruijn numbers, combinators, etc.)?
>>> 
>>> Each lexical variable is given a fresh name (a gensym) when it is
>>> introduced.  The expander keeps an environment as to what name maps to
>>> what gensym, and residualizes the gensym in the lexical reference or
>>> assignment.
>>> 
>>> See "The Scheme Compiler" in the manual, for more.
>> 
>> I am thinking about it in the context of other types of binders, that
>> satisfies the alpha-rule, but not the beta, useful in math (like theorem
>> provers). Has that been discussed?
> 
> Sorry, I don't know what you mean.  References?

There is an article here:
  http://en.wikipedia.org/wiki/Variable_binding_operator

Hans





  reply	other threads:[~2011-04-13 15:46 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-04-13 12:57 Avoiding variable clashes Hans Aberg
2011-04-13 14:19 ` Andy Wingo
2011-04-13 14:34   ` Hans Aberg
2011-04-13 15:27     ` Andy Wingo
2011-04-13 15:46       ` Hans Aberg [this message]
2011-04-13 16:25         ` Noah Lavine
2011-04-13 16:33           ` Hans Aberg
2011-04-13 16:25         ` Andy Wingo
2011-04-13 16:53           ` Hans Aberg
2011-04-14  1:08             ` Noah Lavine
2011-04-14  7:56               ` Andy Wingo
2011-04-14 13:13                 ` Noah Lavine
2011-04-14 14:34                   ` Andy Wingo
2011-04-14  8:30               ` Hans Aberg

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