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<p class="MsoNormal" style="margin-left:36.0pt">At present, Unit# is the only way to turn a lifted type into an unlifted one<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Actually, (# Int, Bool #) does so too. Unboxed one-tuples (currnently called Unit#) is the special case with one argument.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Simon<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US">From:</span></b><span lang="EN-US"> Libraries [mailto:libraries-bounces@haskell.org]
<b>On Behalf Of </b>David Feuer<br>
<b>Sent:</b> 18 January 2018 00:16<br>
<b>To:</b> Andrew Martin <andrew.thaddeus@gmail.com><br>
<b>Cc:</b> Haskell Libraries <libraries@haskell.org><br>
<b>Subject:</b> Re: Name of 1-Tuple Data Type<o:p></o:p></span></p>
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At present, Unit# is the only way to turn a lifted type into an unlifted one. Perhaps<br>
Unlift# or Lower# would make sense? The tricky bit is that one could easily imagine eventually having a version with a strict constructor, in which case it becomes a bit hard to guess which is which.<br>
<br>
On Wed, Jan 17, 2018 at 6:46 PM, Andrew Martin <<a href="mailto:andrew.thaddeus@gmail.com">andrew.thaddeus@gmail.com</a>> wrote:<br>
> Required background information:<br>
> <a href="https://ghc.haskell.org/trac/ghc/ticket/14673">https://ghc.haskell.org/trac/ghc/ticket/14673</a><br>
><br>
> GHC has a one-tuple (both a boxed variant and an unboxed variant). The<br>
> unboxed variant currently must be fully applied whenever it is used. This is<br>
> in stark contrast to all the other n-tuples (n > 1). It stems entirely from<br>
> an issue of syntax. The solution decided on is to provide a normal prefix<br>
> name for the 1-tuple. The name that GHC uses internally for this type is<br>
> `Unit#` (there is also a boxed variant Unit). However, in the haskell<br>
> community, the word "unit" already refers to the nullary tuple, not the<br>
> unary tuple. So, we're bikeshedding the name.<br>
><br>
> Here are some possible options:<br>
><br>
> * Unary (as in unary tuple)<br>
> * Single (as in single, double, triple)<br>
> * Singleton (as is singleton, doubleton, tripleton)<br>
> * Only<br>
> (<a href="https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fhackage.haskell.org%2Fpackage%2FOnly-0.1%2Fdocs%2FData-Tuple-Only.html&data=02%7C01%7Csimonpj%40microsoft.com%7C7d81930a5d3b407cfd7608d55e08b60f%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636518313867711942&sdata=qujBDi9OVAc1Vm68gI%2FK1Yv9us7xtomLwRw9UnUrefo%3D&reserved=0">https://hackage.haskell.org/package/Only-0.1/docs/Data-Tuple-Only.html</a>)<br>
> * OneTuple<br>
> (<a href="https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fhackage.haskell.org%2Fpackage%2FOneTuple-0.2.1%2Fdocs%2FData-Tuple-OneTuple.html&data=02%7C01%7Csimonpj%40microsoft.com%7C7d81930a5d3b407cfd7608d55e08b60f%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636518313867711942&sdata=l7aIxyiWUBdzTHKqTx3%2FkftDWFFlQ1Z4ODlVsNR5wGE%3D&reserved=0">https://hackage.haskell.org/package/OneTuple-0.2.1/docs/Data-Tuple-OneTuple.html</a>)<br>
> * Uni (means "one" in latin or greek or something like that)<br>
> * Mono (means "one" in latin or greek or something like that)<br>
><br>
> I would appreciate any feedback on the suggestions I provided or any<br>
> additional suggestions for the name. If you have concerns about the feature<br>
> itself, comment on the GHC Trac ticket. I'd prefer to keep this thread<br>
> focused on just the problem of coming up with a name.<br>
><br>
> --<br>
> -Andrew Thaddeus Martin<br>
><br>
> _______________________________________________<br>
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><o:p></o:p></p>
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