<div dir="ltr"><div>I haven't followed this debate, but the main question I have is: what are the implications of choosing one view over the other?</div><div><br></div><div>Cheers</div><div>SImon<br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, 13 Nov 2020 at 14:10, Spiwack, Arnaud <<a href="mailto:arnaud.spiwack@tweag.io">arnaud.spiwack@tweag.io</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div><p style="margin:0px 0px 1.2em">Dear all,</p>
<p style="margin:0px 0px 1.2em">There is a debate which has been held in our heads for quite some time now. But we’ve never really had the conversation. This debate has been raised again in the context of proposal #281. But I’d rather make a separate thread about it.</p>
<p style="margin:0px 0px 1.2em">The question is the following:</p>
<p style="margin:0px 0px 1.2em">When I write</p>
<pre style="font-family:Consolas,Inconsolata,Courier,monospace;font-size:1em;line-height:1.2em;margin:1.2em 0px"><code style="font-size:0.85em;font-family:Consolas,Inconsolata,Courier,monospace;margin:0px 0.15em;white-space:pre-wrap;overflow:auto;border-radius:3px;border:1px solid rgb(204,204,204);display:block;padding:0.5em;color:rgb(51,51,51);background:rgb(248,248,248) none repeat scroll 0% 0%"><span style="color:rgb(153,0,0);font-weight:bold">f</span> @t
</code></pre>
<p style="margin:0px 0px 1.2em">Am I using <code style="font-size:0.85em;font-family:Consolas,Inconsolata,Courier,monospace;margin:0px 0.15em;padding:0px 0.3em;white-space:pre-wrap;border:1px solid rgb(234,234,234);background-color:rgb(248,248,248);border-radius:3px;display:inline">@</code> as a way to change an invisible argument into a visible argument? Or am I using <code style="font-size:0.85em;font-family:Consolas,Inconsolata,Courier,monospace;margin:0px 0.15em;padding:0px 0.3em;white-space:pre-wrap;border:1px solid rgb(234,234,234);background-color:rgb(248,248,248);border-radius:3px;display:inline">@</code> to insert a type expression into a term expression?</p>
<hr>
<p style="margin:0px 0px 1.2em">The truth is that it’s doing both at the same time. So some of us have taken to believing that the One True Meaning™ of <code style="font-size:0.85em;font-family:Consolas,Inconsolata,Courier,monospace;margin:0px 0.15em;padding:0px 0.3em;white-space:pre-wrap;border:1px solid rgb(234,234,234);background-color:rgb(248,248,248);border-radius:3px;display:inline">@</code> is to override (in)visibility. While others have taken to believing that the One True Meaning™ of <code style="font-size:0.85em;font-family:Consolas,Inconsolata,Courier,monospace;margin:0px 0.15em;padding:0px 0.3em;white-space:pre-wrap;border:1px solid rgb(234,234,234);background-color:rgb(248,248,248);border-radius:3px;display:inline">@</code> is to insert types in term.</p>
<p style="margin:0px 0px 1.2em">And, in both cases, we believe the other part to be incidental.</p>
<p style="margin:0px 0px 1.2em">In favour of types-in-term, there is the pretty-printer for Core, which, if I’m not mistaken, uses <code style="font-size:0.85em;font-family:Consolas,Inconsolata,Courier,monospace;margin:0px 0.15em;padding:0px 0.3em;white-space:pre-wrap;border:1px solid rgb(234,234,234);background-color:rgb(248,248,248);border-radius:3px;display:inline">@t</code> to denote type applications (and all type applications are visible in Core, so there is no visibility override to be had).</p>
<p style="margin:0px 0px 1.2em">Whatever we think about this, it appears that the fact that this meaning ascription is implicit has caused some anguish. So I think that we should have this discussion explicitly for once.</p>
<p style="margin:0px 0px 1.2em">I chose to do so in a different thread than the #281 discussion, because this discussion stands on its own.</p>
<p style="margin:0px 0px 1.2em">Anyway, the floor is yours.</p>
<p style="margin:0px 0px 1.2em">/Arnaud</p>
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</blockquote></div>