🚀 go-pugleaf

In article <4it51b$ng8@usenet.pa.dec.com>, diamond@tbj.dec.com (Norman Diamond) writes:
|>
|>>>Just one sentence earlier, you gave the exact reason why
|>>>it doesn't matter if you do "a > b" instead of "a - b".
|>
|>>Of course it matters.  With this function, if compar(x,y) > 0, then
|>>compar(y,x) == 0.  This is not antisymmetric.
|>
|>Argh!  I was remembering what the hardware usually does for comparison
|>instructions, and forgot that C operators lose part of that information.
|>I must be getting Cnile.
|>
|>>(a > b)? 1: (a < b)? -1: 0
|>
|>Yup.  Incidentally, do you think the average implementation's
|>interprocedural optimization phase will change this user function into
|>one machine instruction in the library's qsort() function :-?

I'd be quite impressed if it did.

Alternatively, how about this:

    return ((signed int) ((unsigned int)a - (unsigned int)b));

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