<br><div class="gmail_quote">On Thu, Apr 29, 2010 at 3:38 PM, Chris Casinghino <span dir="ltr"><<a href="mailto:chris.casinghino@gmail.com">chris.casinghino@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
With universe polymorphism turned on, it seems that:<br>
<br>
(\ l -> Set l) : (l : Level) -> Set (suc l)<br>
<br>
But<br>
<br>
Set : Set1<br>
<br>
I guess this is just syntax sugar getting in the way of eta reduction?<br></blockquote><div><br></div><div>Set doesn't a have a function type with universe polymorphism (so there's</div><div>nothing to eta contract in your example). Set l is a language construct with</div>
<div>the typing rule</div><div><br></div><div> l : Level</div><div>-------------------------</div><div>Set l : Set (suc l)</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
Agda's explicit universe polymorphism is a lot of fun to play with.<br>
Is it documented anywhere?<br></blockquote><div><br></div><div>Not really. Universe polymorphism is still very experimental and could be</div><div>subject to change at any time. </div><div><br></div><div>/ Ulf</div></div>