<!DOCTYPE html><html><head><title></title><style type="text/css">p.MsoNormal,p.MsoNoSpacing{margin:0}</style></head><body><div>It has been two weeks since I submitted this proposal, and one week since the core library committee started deliberating behind closed doors. Is there any visibility into the CLC's process, or at the very least a rough expected timeline?<br></div><div><br></div><div>On Fri, Aug 23, 2019, at 3:57 AM, Sven Panne wrote:<br></div><blockquote type="cite" id="qt"><div dir="ltr"><div dir="ltr">Am Do., 22. Aug. 2019 um 19:11 Uhr schrieb Kris Nuttycombe <<a href="mailto:kris.nuttycombe@gmail.com">kris.nuttycombe@gmail.com</a>>:<br></div><div class="qt-gmail_quote"><blockquote style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0.8ex;border-left-color:rgb(204, 204, 204);border-left-style:solid;border-left-width:1px;padding-left:1ex;" class="qt-gmail_quote"><div dir="ltr"><div dir="ltr"><br></div><div class="qt-gmail_quote"><div class="qt-gmail_attr" dir="ltr">On Thu, Aug 22, 2019 at 3:58 AM Sven Panne <<a href="mailto:svenpanne@gmail.com">svenpanne@gmail.com</a>> wrote:<br></div><blockquote style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0.8ex;border-left-color:rgb(204, 204, 204);border-left-style:solid;border-left-width:1px;padding-left:1ex;" class="qt-gmail_quote"><div dir="ltr"><div class="qt-gmail_quote"><div class="qt-gmail_attr" dir="ltr"> I think there's a significant difference between "little helper" and "the monomorphic function that is used to implement `pure`" - with a slightly different framing, we might be able to come to an agreement that both the monomorphic an polymorphic versions of this function are useful in different contexts. [...]<br></div></div></div></blockquote></div></div></blockquote><div><br></div><div>I think we can agree that we disagree here. ;-) My brain is too small to remember the names of myriads of trivial helpers, so I very much prefer general, orthogonal things. In our case: If we have a general, polymorphic function (often from a type class), just use that. If for some reason (rarely!) I want a more monomorphic function, I can just add a plain old type signature somewhere (no need for funky language extensions like type applications). This radically reduces the number of things one has to remember. In our case: Know type classes + know a way to make things more monomorphic.<br></div><div> <br></div><blockquote style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0.8ex;border-left-color:rgb(204, 204, 204);border-left-style:solid;border-left-width:1px;padding-left:1ex;" class="qt-gmail_quote"><div dir="ltr"><div class="qt-gmail_quote"><blockquote style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0.8ex;border-left-color:rgb(204, 204, 204);border-left-style:solid;border-left-width:1px;padding-left:1ex;" class="qt-gmail_quote"><div dir="ltr"><div class="qt-gmail_quote"><div class="qt-gmail_attr" dir="ltr"><br></div></div></div></blockquote><div>My guiding principle for API design is that one should always expose the fundamental building blocks as a low-level API, and then provide a smaller interface for the common use cases. Typeclass instances are no different - they are the general interface that allows us to invoke what is ultimately a monomorphic, low-level building block function in a polymorphic context. <br></div></div></div></blockquote><div><br></div><div>This is exactly the opposite API design principle I have: Do not expose the monomorphic functions if they are already in a type class. You can easily reconstruct them as a library user via type signtures if this is really needed (still haven't seen many convincing examples of that), but you can' do it the other way round. Less things exposed, no generality/use cases lost => easier to remember.<br></div><div><br></div><div>The thing we can probably agree on: API design is hard and it's not an exact science, more a kind of art which is assessed in a subjective way... :-)<br></div><blockquote style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0.8ex;border-left-color:rgb(204, 204, 204);border-left-style:solid;border-left-width:1px;padding-left:1ex;" class="qt-gmail_quote"><br></blockquote></div></div><div>_______________________________________________<br></div><div>Libraries mailing list<br></div><div>Libraries@haskell.org<br></div><div>http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries<br></div><div><br></div></blockquote><div><br></div></body></html>