<div dir="auto">Agreed! I’ve actually never met somone who suggests it as either a starter or advanced reference e</div><div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Apr 14, 2021 at 8:43 AM Dominic Steinitz <<a href="mailto:dominic@steinitz.org">dominic@steinitz.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div style="word-wrap:break-word;line-break:after-white-space"><div>I’d recommend *not* reading Categories for the Working Mathematician unless you are a mathematician (lots of background assumed) and even then it’s a bit of a dull read.</div><div><br></div><div>
<div style="color:rgb(0,0,0);font-family:Helvetica;font-size:12px;font-style:normal;font-variant-caps:normal;font-weight:normal;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;text-decoration:none">Dominic Steinitz<br><a href="mailto:dominic@steinitz.org" target="_blank">dominic@steinitz.org</a><br><a href="http://idontgetoutmuch.org" target="_blank">http://idontgetoutmuch.org</a><br>Twitter: @idontgetoutmuch</div>

</div>
<br><div><blockquote type="cite"><div><div>From: Viktor Dukhovni <<a href="mailto:ietf-dane@dukhovni.org" target="_blank">ietf-dane@dukhovni.org</a>><br>To: <a href="mailto:haskell-cafe@haskell.org" target="_blank">haskell-cafe@haskell.org</a><br>Subject: Re: [Haskell-cafe] Haskell function composition commutivity?<br>Message-ID: <<a href="mailto:YHYPMnJcYzdEolzl@straasha.imrryr.org" target="_blank">YHYPMnJcYzdEolzl@straasha.imrryr.org</a>><br>Content-Type: text/plain; charset=us-ascii<br><br>On Tue, Apr 13, 2021 at 02:19:46PM -0500, Galaxy Being wrote:<br><br><blockquote type="cite">Your answers seem to originate outside of normal Haskell tutorials. Where<br>can I start with this higher superset theory?<br></blockquote><br>There's a reason why the tutorials don't cover this, the categorical<br>foundations of Haskell types are not beginner material.  It is perhaps<br>best to defer going down this rabbit hole until you're more comfortable<br>with the Haskell generally.<br><br>You could start with:<br><br>    <a href="https://bartoszmilewski.com/2014/10/28/category-theory-for-programmers-the-preface/" target="_blank">https://bartoszmilewski.com/2014/10/28/category-theory-for-programmers-the-preface/</a><br>    <a href="https://bartoszmilewski.com/2015/04/07/natural-transformations/" target="_blank">https://bartoszmilewski.com/2015/04/07/natural-transformations/</a><br><br>For the Yoneda Lemma specifically, I'd recommend:<br><br>    <a href="http://blog.sigfpe.com/2006/11/yoneda-lemma.html" target="_blank">http://blog.sigfpe.com/2006/11/yoneda-lemma.html</a><br><br>Parametricity is covered in "Theorems for free":<br><br>    <a href="https://www2.cs.sfu.ca/CourseCentral/831/burton/Notes/July14/free.pdf" target="_blank">https://www2.cs.sfu.ca/CourseCentral/831/burton/Notes/July14/free.pdf</a><br><br>but it is by no means elementary, though skimming it for the essential<br>facts and skipping the gory details is not too difficult.<br><br>You could also read "Categories for the Working Mathematician" by<br>Saunders Mac Lane.<br></div></div></blockquote></div><br></div>_______________________________________________<br>
Haskell-Cafe mailing list<br>
To (un)subscribe, modify options or view archives go to:<br>
<a href="http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe" rel="noreferrer" target="_blank">http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe</a><br>
Only members subscribed via the mailman list are allowed to post.</blockquote></div></div>