dynamic module creation

dynamic module creation

[Julian Graham]

Hi Guilers,

Is there a way to create a module at runtime and evaluate expressions
in it using a dynamically-created set of module imports?  I want to do
something along the lines of:

(save-module-excursion
  (lambda ()
    (define-module (my-dynamic-module-name)
      #:use-module (a-module-i-decided-to-include-at-runtime)
      #:pure)
    (do-something)))

...except `define-module' doesn't like being called from anywhere
except the top level.  I also tried `resolve-module', the
documentation for which says:

 Find the module named NAME and return it.  When it has not already
 been defined, try to auto-load it.  When it can't be found that way
 either, create an empty module.

This works as advertised -- it really does create an empty module, but
it's completely empty: No core Scheme syntax, not even any syntactic
sugar like '@ to help you get at stuff from the core.  It's an utterly
blank environment.  Is there some way to get the module-creation
behavior of `resolve-module' but also be able to include stuff from
other modules in the resulting environment?


Regards,
Julian

Re: dynamic module creation

[Andy Wingo]

On Sun 01 Feb 2009 08:58, Julian Graham <joolean@gmail.com> writes:

> Is there some way to get the module-creation
> behavior of `resolve-module' but also be able to include stuff from
> other modules in the resulting environment?

guile> (resolve-module '(foo))
$1 = #<directory (foo) b7f11bb0>
guile> (beautify-user-module! $1)
$2 = (#<interface (guile) b7f8aef0>)
guile> (module-ref $1 'sin)
$3 = #<procedure sin (z)>
guile> 

Cheers,

Andy
-- 
http://wingolog.org/

Re: dynamic module creation

[Neil Jerram]

Andy Wingo <wingo@pobox.com> writes:

> On Sun 01 Feb 2009 08:58, Julian Graham <joolean@gmail.com> writes:
>
>> Is there some way to get the module-creation
>> behavior of `resolve-module' but also be able to include stuff from
>> other modules in the resulting environment?
>
> guile> (resolve-module '(foo))
> $1 = #<directory (foo) b7f11bb0>
> guile> (beautify-user-module! $1)
> $2 = (#<interface (guile) b7f8aef0>)
> guile> (module-ref $1 'sin)
> $3 = #<procedure sin (z)>
> guile> 

And for an example of this, see `use-elisp-file' in
lang/elisp/interface.scm.

        Neil

Re: dynamic module creation

[Ludovic Courtès]

Hi,

Andy Wingo <wingo@pobox.com> writes:

> On Sun 01 Feb 2009 08:58, Julian Graham <joolean@gmail.com> writes:
>
>> Is there some way to get the module-creation
>> behavior of `resolve-module' but also be able to include stuff from
>> other modules in the resulting environment?
>
> guile> (resolve-module '(foo))
> $1 = #<directory (foo) b7f11bb0>

You could also use:

  (let ((m (make-module)))
    (set-module-name! m '(foo))
    m)

but you still need this ugly part:

> guile> (beautify-user-module! $1)
> $2 = (#<interface (guile) b7f8aef0>)

Thanks,
Ludo'.

Re: dynamic module creation

[Neil Jerram]

Julian Graham <joolean@gmail.com> writes:

> Incidentally, my naive attempt to refine the behavior of
> `beautify-user-module!' straight-up failed:
>
> guile> (define m (resolve-module '(foo)))
> guile> (let ((interface (make-module 31)))
> ... (set-module-name! interface (module-name m))
> ... (set-module-kind! interface 'interface)
> ... (set-module-public-interface! m interface))
> #f
> guile> (set-module-uses! m '((guile) :select (if)))
> ((guile) :select (if))
> guile> (set-current-module m)
> #<directory (guile-user) b7d61630>
> guile> if
> Segmentation fault

I haven't managed to test this yet, but I think your
`(set-module-uses! m '((guile) :select (if)))' should be
`(set-module-uses! m (list (resolve-interface '(guile) #:select '(if))))'.

(And we should also add type-checking to set-module-uses!)

Regards,
        Neil