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Re: [Scheme-reports] Import declarations in programs

Alex Shinn <alexshinn@x> writes:

> On Wed, Jan 22, 2014 at 3:56 AM, Jim Rees <jimreesma@x> wrote:
>> On Tue, Jan 21, 2014 at 6:14 AM, Marc Nieper-Wißkirchen <
>> marc.nieper@x> wrote:
>>> 1) Why is more than one import declaration allowed in a Scheme program?
>> This looks like a residual outcome where it was left open in
>> http://trac.sacrideo.us/wg/ticket/473 until the resolution of 472 (on
>> whether include,include-ci,cond-expand could expand into import forms).
>>  The decision there ended up being a "no" from how I read it - so the only
>> motivation for permitting multiple import declarations seemed to vanish
>> there, but I guess tightening the spec down got lost in the shuffle.  Maybe
>> there was yet another motivation?
> Good research.  Yes, multiple imports are no longer
> needed and can be ambiguous.  I think the only
> motivation for this would be the hope that a future standard
> would allow top-level includes and cond-expands to expand
> into imports.
> In the meantime, the solution to avoid ambiguity is
> easy - if you import an `import', make sure you do it
> last.  This is trivially satisfied by only ever using one
> import form.

Sorry for being dense here, as I'm a bit out of touch, but which import
form are we talking about? I was under the impression that we cleared up
any questions of scoping and bindings for the import forms of libraries
and the like? I thought that with a library or other program, the import
forms were clearly static and outside of the scope of any environments
defined by those import forms? I thought that we made it explicit that
import forms and the like could appear in any order, as well. 

There are plenty of motivations for using multiple import forms, but I
just want to make sure I understand the complaint? I thought that we
very intentionally kept and allowed multiple import and export forms?

Aaron W. Hsu | arcfide@x | http://www.sacrideo.us
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