Re: Module reflection and the list of bound symbols

[Ian Price <ianprice90@googlemail.com>]

Panicz Maciej Godek <godek.maciek@gmail.com> writes:

> On the other hand, there is no way (or I haven't found one)
> to list the bound symbols explicitly. It seems tempting to
> have a reflection function `module-symbols' or `environment-symbols'
> that would return the names of bound symbols,
> or to have functions like environment->list or module->list that
> would return assoc lists mapping symbols to their values.
Hmm, no, but you are able to get the "obarray" for the module which is a
hash of symbols -> variables.

(define (hash-keys hash)
  (hash-fold (lambda (key val prev)
               (cons key prev))
             '()
             hash))

(define (module-exports module)
  (hash-keys (module-obarray module)))

scheme@(guile−user)> (module-exports (resolve-module '(pfds queues)))
$20 = (queue−>list queue−empty−condition? enqueue &queue−empty
queue−length make−queue rotate queue−l∧ dummy queue−l
make−queue−empty−condition %module−public−interface list−>queue
dequeue queue−empty? queue? queue %make−queue queue−r makeq)

This lists _all_ the bindings, even the non-public ones.

I'm sure there is a way to get only the public (exported) ones using the
interfaces, but that is beyond my knowledge at the moment.

-- 
Ian Price -- shift-reset.com

"Programming is like pinball. The reward for doing it well is
the opportunity to do it again" - from "The Wizardy Compiled"