defined? in module

defined? in module

[Daniel Kraft]

Hi,

I'm trying to check if a given name is bound within some module.  It 
seems (from the documentation) that module objects are considered 
environments; but this does not work:

scheme@(guile-user)> (defined? 'abc (current-module))

Backtrace:
In unknown file:
    ?: 0* [#<vm b7a8e650> #<program b70ac450 at <unknown port>:1:0 ()>]
    2: 1* [#<program b70ac450 at <unknown port>:1:0 ()>]
    ?: 2* [defined? abc {#<directory (guile-user) 80bb3f0>}]

ERROR: In procedure defined?:
ERROR: Wrong type argument in position 2: #<directory (guile-user) 80bb3f0>

So, what's wrong here and how to do this correctly?  (I know that 
testing for 'abc in current-module is trivial, but say I want to find 
out about 'abc in (language elisp runtime value-slot) for instance.)

BTW, finally, I want to do this in Tree-IL.  But if I manage to do it in 
Scheme, changing to Tree-IL is trivial.

Thanks a lot,
Daniel

Re: defined? in module

[Ludovic Courtès]

Hello Daniel,

I realized this question was left unanswered.

Daniel Kraft <d@domob.eu> writes:

> I'm trying to check if a given name is bound within some module.  It
> seems (from the documentation) that module objects are considered
> environments; but this does not work:
>
> scheme@(guile-user)> (defined? 'abc (current-module))

You want to use `module-defined?':

--8<---------------cut here---------------start------------->8---
scheme@(guile-user)> (module-defined? (current-module) '+)
#t
--8<---------------cut here---------------end--------------->8---

The second argument to `defined?' is probably only valid in the context
of the evaluator:

--8<---------------cut here---------------start------------->8---
guile> (version)
$1 = "1.8.6"
guile> (defined? '+ (the-environment))
$2 = #t
guile> (let ((x 2))
         (defined? 'x (the-environment)))
$3 = #t
--8<---------------cut here---------------end--------------->8---

Maybe `defined?' should be changed in 1.9 to accept a module as its
second argument?

Thanks,
Ludo'.

Re: defined? in module

[Andy Wingo]

On Fri 17 Jul 2009 16:54, ludo@gnu.org (Ludovic Courtès) writes:

> Maybe `defined?' should be changed in 1.9 to accept a module as its
> second argument?

Makes sense to me, yes.

Andy
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