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Re: A module system question.

mike@olan.com (Michael N. Livshin) writes:

> Is there a way for a function to know in which module it is defined?
> 
> To clarify:
> 
> (define-module (used-module))
> 
> (define-public (fun)
>   (my-module))
>   ^^^^^^^^^^^
> 
> (define-module (using-module)
>   #:use-modules (used-module))
> 
> (fun)
>      => returns (used-module)
> 
> Is there any way to write the `my-module' function?

Yes.  Guile has something called the `current' module.  While a
certain module is being defined, that module is the current one.
However, when a function that is contained in a certain module is
actually called, the current module will *not* be the one that the
function is contained in.

So, the following will work

    (define-module (used-module))

    (define this-module (current-module))

    (define (my-module)
      this-module)

    (define-public (fun)
      (my-module))


    (define-module (using-module)
      #:use-module (used-module))

    (fun)
	 => returns #<directory used-module 61b98>

But this will *not* work:

    (define-module (used-module))

    (define (my-module)
      (current-module))

    (define-public (fun)
      (my-module))