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<div class="">On Jan 26, 2023, at 9:36 AM, Brian Goetz <<a href="mailto:brian.goetz@oracle.com" class="">brian.goetz@oracle.com</a>> wrote:</div>

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For comparing a variable to a constant, representational equality is the obvious interpretation; `case nnn` means "is it the number nnn".  This allows you to say `case NaN` and `case -0` and get the right answer (all of these relations agree on what to do about

 1.0).  <br class="">

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<div>Careful: I think you had better say “<font face="Menlo" class=""><span style="font-style: normal;" class="">case -0.0</span></font>”; otherwise the constant expression “<font face="Menlo" class=""><span style="font-style: normal;" class="">-0</span></font>”

 will be reduced to “<font face="Menlo" class=""><span style="font-style: normal;" class="">0</span></font>” and only then converted to floating-point representation, producing

<font face="Menlo" class=""><span style="font-style: normal;" class="">+0.0</span></font>.</div>

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Yes, floating-point is VERY fiddly.

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<div class="">—Guy</div>

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