[plt-scheme] eval-string namespace

I think that you have a fundamental misunderstanding about what eval
does. Without some context of your real problem it is hard to offer any
suggestions.

Robby

At 30 Jul 2003 12:33:46 +0000, Paulo Jorge de Oliveira Cantante de Matos wrote:
>   For list-related administrative tasks:
>   http://list.cs.brown.edu/mailman/listinfo/plt-scheme
> 
> Hi again,
> 
> Ok, my situation seems now to be even worse.
> I've provided all my functions, still I'm not able to call them from
> toplevel. Check the following simple example:
> caller.scm:
> (module caller mzscheme
>   
>   (require "test.scm")
>   
>   (define (call-it)
>     (bar))
>   
>   (provide call-it))
> 
> test.scm:
> (module test mzscheme
>   
>   (require (lib "string.ss"))
>   
>   (define (foo)
>     (eval-string (read-line)))
>   
>   (define (bar)
>     (display "Done"))
>   
>   (provide foo bar))
> 
> Now I execute caller.scm:
> > (require "caller.scm")
> > (call-it)
> (bar)
> 
> . . reference to undefined identifier: bar
> 
> 
> Why can't I call bar if they are on toplevel (since I provided them)?
> Can't foo and bar be inside a module for me to call them?
> 
> Best regards,
> 
> Paulo Matos
> 
> >From: Robby Findler <robby at cs.uchicago.edu>
> >To: Paulo Jorge de Oliveira Cantante de Matos <pocm at mega.ist.utl.pt>
> >Cc: PLT Scheme ML <plt-scheme at list.cs.brown.edu>
> >Subject: Re: [plt-scheme] eval-string namespace
> >Date: Tue, 29 Jul 2003 16:24:20 -0500
> >
> >When you provide bar, the `require' is putting bar into the toplevel
> >namespace. Also, when you call eval-string, that code will refer to the
> >toplevel namespace. If you don't provide bar, then it won't be in the
> >toplevel namespace, so the eval-string won't find it.
> >
> >The point here is that `eval-string' is not lexically sensitive in any
> >way. It always compiles free identifiers in the input expression to
> >refer to the toplevel -- not the place where the eval-string was
> >called.
> >
> >Robby
> >
> >At 29 Jul 2003 22:15:29 +0000, Paulo Jorge de Oliveira Cantante de
> >Matos wrote:
> >>   For list-related administrative tasks:
> >>   http://list.cs.brown.edu/mailman/listinfo/plt-scheme
> >> 
> >> Hi all,
> >> 
> >> Check the following:
> >> (module test mzscheme
> >>   
> >>   (require (lib "string.ss"))
> >>   
> >>   (define (foo)
> >>     (eval-string (read-line)))
> >>   
> >>   (define (bar)
> >>     (display "Done"))
> >>   
> >>   (provide foo))
> >> 
> >> If I run this, require test.scm and enter bar for read-line I get
> that
> >> bar is undefined. But it'll work alright if I provide bar. Why? 
> >> I don't understand this behaviour, it's definitely not what I
> expected.
> >> In the manual there is no mention to this situation, which is I might
> >> say strange and boring since I have in the module 20 functions that
> can
> >> be called through eval-string that I don't want to provide.
> >> 
> >> Any suggestions?
> >> 
> >> Best regards,
> >> 
> >> Paulo J. Matos
> >> 
> >> 
> 
> 
>