How do you decide whether a key-extractor block returns number? Do you look at the signature, or do you simply evaluate the result of the key-extractor for each element in the unsorted list? For example, what is the result of the following code?
sort {$_.key} (1=> 'a', 10 => 'b', 2 =>'c');
There is nothing in the signature of the key-extractor to suggest that all the keys are numbers, but as it turns out they all are. Will the sort end up being numerical or alphabetic?
Whilst I'd very much like it to analyse the keys, detect that they're all numbers, and use C<< <=> >>, I suspect that if C<sort> can't determine that the return type of the key extractor is numeric, it will have to default to C<cmp>. Otherwise a case like this:
sort {$_.key} (1=> 'a', 10 => 'b', '2' =>'c');
becomes a little too subtle.
And, after all, it isn't that much extra work to force the issue:
sort {+$_.key} (1=> 'a', 10 => 'b', 2 =>'c');
vs:
sort {~$_.key} (1=> 'a', 10 => 'b', 2 =>'c');Damian
