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Re: [Chicken-users] basic Scheme question

From: Shawn Rutledge
Subject: Re: [Chicken-users] basic Scheme question
Date: Thu, 23 Oct 2008 23:54:03 -0700

On Thu, Oct 23, 2008 at 11:44 PM, Peter Bex <address@hidden> wrote:
> On Thu, Oct 23, 2008 at 10:27:18PM -0700, Shawn Rutledge wrote:
>> #;10> (begin (define update #f) (let ([v 'foo]) (set! update (lambda
>> (d s) (printf "~s was ~s~%" d (eval d)) (set! d s)))))
>> #;11> (update 'v 'bar)
>> Error: unbound variable: v
>> What I'm trying to do is pass the name of a let-bound variable in to a
>> lambda defined within the let context, in order to tell that lambda to
>> access that let-bound variable.  eval doesn't work because it looks in
>> the outer environment, right?  (in which v is not bound)
> Eval only sees the top-level environment.  It may be possible to use
> the environments egg to construct your own environment containing v.

I thought of that, but also thought there must be a generic Scheme way
to do this.

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