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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US">If there is to be such a language feature, I strongly feel it should be via something like<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US"> module Long.Name.M( f, g, h )
<b>as K</b> where ...<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US">I do not want to try to piggy-back on the possible meaning of a self-import; it’s just asking for trouble, as Iavor points out.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US">Using “as M” in the module header would be simple. It is easy to explain and fairly easy to implement. I don’t think there are
any knock-on complications. So if enough people want it, and someone is prepared to implement it (with a language extension flag of course), then I’d be OK with that. I’m unsure that it’s worth the effort, but I’m happy to let users decide.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US">Simon<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif"">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif""> Glasgow-haskell-users [mailto:glasgow-haskell-users-bounces@haskell.org]
<b>On Behalf Of </b>Iavor Diatchki<br>
<b>Sent:</b> 30 September 2014 13:18<br>
<b>To:</b> john@repetae.net<br>
<b>Cc:</b> GHC Users Mailing List; ghc-devs; Herbert Valerio Riedel<br>
<b>Subject:</b> Re: Aliasing current module qualifier<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p>Hello,<o:p></o:p></p>
<p>What semantics are you using for recursive modules? As far as I see, if you take a least fixed point semantics (e.g. as described in "A Formal Specification for the Haskell 98 Module System",
<a href="http://yav.github.io/publications/modules98.pdf">http://yav.github.io/publications/modules98.pdf</a> ) this program is incorrect as the module does not export anything.<o:p></o:p></p>
<p>While this may seem a bit counter intuitive at first, this semantics has the benefit of being precise, easily specified, and uniform (e.g it does not require any special treatment of the " current " module). As an example, consider the following variation
of your program, where I just moved the definition in a sperate (still recursive) module:<o:p></o:p></p>
<p>module A (M.x) where<br>
import B as M<o:p></o:p></p>
<p>module B (M.x) where<br>
import A as M<br>
x = True<o:p></o:p></p>
<p>I think that it'd be quite confusing if a single recursive module worked differently then a larger recursive group, but it is not at all obvious why B should export 'x'. And for those who like this kind of puzzle: what should happen if 'A' also had a definition
for 'x'?<o:p></o:p></p>
<p>Iavor<o:p></o:p></p>
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<p class="MsoNormal">On Sep 29, 2014 11:02 PM, "John Meacham" <<a href="mailto:john@repetae.net">john@repetae.net</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">You don't need a new language construct, what i do is:<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#500050"> module AnnoyinglyLongModuleName (M.length, M.null) where</span><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#500050"> import AnnoyinglongLongModuleName as M</span><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#500050">I think ghc would need to be extended a little to make this convienient as it doesn't handle recursive module imports as transparently.</span><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#500050"> John</span><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Mon, Sep 29, 2014 at 8:47 AM, Brandon Allbery <<a href="mailto:allbery.b@gmail.com" target="_blank">allbery.b@gmail.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">On Mon, Sep 29, 2014 at 4:19 AM, Herbert Valerio Riedel <<a href="mailto:hvr@gnu.org" target="_blank">hvr@gnu.org</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">Now it'd be great if I could do the following instead:<br>
<br>
module AnnoyinglyLongModuleName (M.length, M.null) where<br>
<br>
import AnnoyinglyLongModuleName as M -- <- does not work<o:p></o:p></p>
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I think if I wanted this syntax, I'd go for:<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"> module AnnoyinglyLongModuleName as M where ...<span style="color:#888888"><br clear="all">
<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:#888888"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="color:#888888">-- <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:#888888">brandon s allbery kf8nh sine nomine associates<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:#888888"><a href="mailto:allbery.b@gmail.com" target="_blank">allbery.b@gmail.com</a> <a href="mailto:ballbery@sinenomine.net" target="_blank">ballbery@sinenomine.net</a><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:#888888">unix, openafs, kerberos, infrastructure, xmonad <a href="http://sinenomine.net" target="_blank">http://sinenomine.net</a><o:p></o:p></span></p>
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_______________________________________________<br>
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<a href="http://www.haskell.org/mailman/listinfo/glasgow-haskell-users" target="_blank">http://www.haskell.org/mailman/listinfo/glasgow-haskell-users</a><o:p></o:p></p>
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<br clear="all">
<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-- <br>
John Meacham - <a href="http://notanumber.net/" target="_blank">http://notanumber.net/</a>
<o:p></o:p></p>
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_______________________________________________<br>
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