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<div class="moz-cite-prefix">On 9/13/2022 9:55 AM, Brian Goetz
wrote:<br>
</div>
<blockquote type="cite" cite="mid:5bf2de36-4e56-cb68-2fe3-972d4cadebb8@oracle.com">
<br>
<blockquote type="cite">It is common for math library methods to
have a preamble to screen out special values (infinities, NaN,
0.0, 1.0, etc.).
<br>
<br>
This would be a reasonable use of a switch on float/double
switch.
<br>
<br>
<br>
</blockquote>
<br>
Which raises some questions (again) of the semantics of constant
patterns for exotic floating point values, especially (again)
negative zero.
<br>
</blockquote>
<p><br>
</p>
<p>In a switching context, I think there is a stronger case for
distinguishing between +0.0 and -0.0. The operational semantics
I'd recommend are to desugar, say a float switch, to an int switch
on the Float.<span class="element-name">floatToIntBits mapping of
the float case labels. </span><span class="element-name">Float.<span class="element-name">floatToIntBits, as opposed to </span></span><span class="element-name"><span class="element-name"><span class="element-name">Float.<span class="element-name">floatToRawIntBits,
normalized all NaN representations to a single value.</span></span></span></span></p>
<p>-Joe<br>
</p>
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