[plt-scheme] let-require

Amen

On Mon, Nov 2, 2009 at 12:16 PM, Grant Rettke <grettke at acm.org> wrote:
> PLaneT is an underutilized treasure trove. The model makes it easy for
> great contributions; but who knows about them?
>
> On Mon, Nov 2, 2009 at 12:24 PM, Carl Eastlund <carl.eastlund at gmail.com> wrote:
>> I provide this in a planet package:
>>
>> --
>> #lang scheme
>>
>> (require (planet cce/scheme:6))
>>
>> (define (make-weird-list a b c)
>>  (local-require srfi/1)
>>  (circular-list a b c))
>>
>> (define (circular-list . args)
>>  (error "Never gets here"))
>>
>> (make-weird-list 1 2 3)
>> --
>>
>> Carl Eastlund
>>
>> On Mon, Nov 2, 2009 at 1:13 PM, Synx <plt at synx.us.to> wrote:
>>>
>>> You know what would be awesome? A syntax that lets you require a module
>>> but limits the lexical scope of its provided names. Something like:
>>>
>>> ---
>>> (define (make-weird-list a b c)
>>>  (let-require (srfi/1)
>>>    (circular-list a b c)))
>>>
>>> (define (circular-list . args)
>>>  (error "Never gets here"))
>>>
>>> (make-weird-list 1 2 3)
>>> ---
>>>
>>> or one thing I was thinking is to allow multiple modules in one file,
>>> yet only the one named according to the file name is available from
>>> external files.
>>>
>>> weird-list.ss
>>> ---
>>> (module backstage scheme/base
>>>  (require srfi/1)
>>>  (define (make-thing a b c)
>>>    (circular-list a b c))
>>>  (provide make-thing))
>>>
>>> (module weird-list scheme/base
>>>  (require backstage)
>>>  (define (main)
>>>    (make-thing 1 2 3))
>>>  (provide main))
>>> ---
>>>
>>> I like the let-require idea better though. Is there a reason that
>>> require must introduce names at the module's lexical scope? Or is there
>>> a way to do it already that I don't know about?
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>>
>
>
>
> --
> http://www.wisdomandwonder.com/
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-- 
Jay McCarthy <jay at cs.byu.edu>
Assistant Professor / Brigham Young University
http://teammccarthy.org/jay

"The glory of God is Intelligence" - D&C 93