I keep on seeing people saying this, and here I am thinking to myself, "Gee, and here I would only give myself even odds of getting #6 right." I know what the operator is for, I know how to use it perfectly well as a sort function, I know how to use complex combinations to do sorts on complex data.

But do I know whether the comparison function is supposed to return a 1 or -1 to sort to say that the left side is smaller than the right this time...? I could guess but I never remember that. If I really need to know it, I can look it up any time. All that I need to know the vast majority of the time is that whatever way it goes, sort and the comparison functions agree on how it is done. (And this tidbit is of a kind I find hard - for instance I still have to think about whether in a LEFT JOIN the table you want to fill in blanks for should be on the left or the right.)

EDIT AUG 2009 Somehow this node got badly messed up. I've filled in the end with what I think is my original thought, but it is unlikely to be right. :-(

In reply to Re: Re: A Perl aptitude test by tilly
in thread A Perl aptitude test by Jonathan

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