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Re: [Scheme-reports] Import declarations in programs

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.


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