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From: Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups: comp.lang.javascript
Subject: Re: How would you prepare for javascripting interview?
Date: Mon, 05 Sep 2016 20:32:34 +0100
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ram@zedat.fu-berlin.de (Stefan Ram) writes:

> Scott Sauyet <scott@sauyet.com> writes:
>>Well, it's easy enough to imagine an infinite collection, say, of all the 
>>positive rational numbers whose squares are less than 2.  There's an 
>>obvious finite maximum in the real numbers, sqrt(2).  See Dedekind cuts 
>>for more information.  [1]
>
>   /Supremum/. The /maximum/ of a set is an /element/ of that set,
>   but sqrt(2) is not a number whose square is /less than/ 2.

Curiously, you've been arguing for a definition of maximum where it may
/not/ be an element of the set.

Further, when sup is defined on the extended reals (R U {-oo, +oo}) so
that sup R = oo, it makes sense to define sup {} = -oo (and some authors
actually do this).

So here you seem to arguing that Math.max() = -Infinity is wrong because
the maximum of a set is an element of that set, but there should be a
Math.sup() whose value is -Infinity.

-- 
Ben.