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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 22:13:18 +0100
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Scott Sauyet <scott@sauyet.com> writes:

> Doc O'Leary wrote:
>> Scott Sauyet wrote:
>
>>> Remember that the context was the functions `Math.max` and `Math.min`,
>>> so a number-centric implementation makes perfect sense.
>> 
>> No, it doesn’t.  It makes *zero* sense for either function to return a
>> number that wasn’t in the input set.  That’s just a bad decision in the
>> language’s design.  
>
> I disagree.  The realistic choices are
>
>   (A) Return something of the correct type, even though it's not 
>       in the (empty) input list.
>
>   (B) Return some semaphore of a different type that signals that 
>       things have gone wrong: `undefined` or `null` are most likely.
>
>   (C) Throw an error.
>
> None of these choices is ideal, but we have to choose between them.  I'd
> say that the best ordering is A > C > B.

I'd also distinguish a B/A option which is to return a value of a type
derived from that of the list (or arguments).  It's the ML/Haskell
way[1] -- you return a 'Maybe Number' object that is either 'Nothing' or
'Just m' (where m is the number found).

I realise you may have drawn up your list specifically in the context of
ECMAScript where such a type is much less handy (though we now have
destructuring bindings), but I thought I'd throw it into the mix anyway.

[1] Though it's not used, as it happens, for 'maximum' in Haskell which
opts for your (C).

<snip>
-- 
Ben.