Can't get outside bindings in the string expression with eval-string

Can't get outside bindings in the string expression with eval-string

[Nala Ginrut]

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hi guys, I want to get a variable bidden from outside environment, such as
the code below:

-----------------------correct code------------------------
(define fp (open-output-file "/tmp/aaa"))
(eval-string "(write 123 fp)" (current-module))
-------------------------end----------------------------------

This code can run successfully.

But I want to use this trick in a procedure:
-----------------------wrong code------------------------------
(define (func)
   (let ((fp (open-output-file "/tmp/aaa")))
       (eval-string "(write 123 fp)" (current-module))
    ))
-----------------------end code------------------------------------

Guile will throw :
========================================
scheme@(guile-user)> (func)
ERROR: In procedure memoize-variable-access!:
ERROR: Unbound variable: fp0
========================================

Is this a bug? Or I missed something?

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Re: Can't get outside bindings in the string expression with eval-string

[Nala Ginrut]

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sorry for the typo:
s/bidden/bound/g

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Re: Can't get outside bindings in the string expression with eval-string

[Andy Wingo]

On Tue 18 Oct 2011 16:32, Nala Ginrut <nalaginrut@gmail.com> writes:

> -----------------------wrong code------------------------------
> (define (func)
>    (let ((fp (open-output-file "/tmp/aaa")))
>        (eval-string "(write 123 fp)" (current-module))
>     ))
> -----------------------end code------------------------------------

`fp' is a lexical binding, not a module-level binding.  So no, this
won't work.  You won't be able to get to lexical variables via `eval'
(or `eval-string').

Andy
-- 
http://wingolog.org/

Re: Can't get outside bindings in the string expression with eval-string

[Nala Ginrut]

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On Tue, Oct 18, 2011 at 10:59 PM, Andy Wingo <wingo@pobox.com> wrote:

> On Tue 18 Oct 2011 16:32, Nala Ginrut <nalaginrut@gmail.com> writes:
>
> > -----------------------wrong code------------------------------
> > (define (func)
> >    (let ((fp (open-output-file "/tmp/aaa")))
> >        (eval-string "(write 123 fp)" (current-module))
> >     ))
> > -----------------------end code------------------------------------
>
> `fp' is a lexical binding, not a module-level binding.  So no, this
> won't work.  You won't be able to get to lexical variables via `eval'
> (or `eval-string').
>
> Andy
> --
> http://wingolog.org/
>


OK, I'll try another approach.

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