Re^2: Sorting result of function call

[Hofmator]

in reply to Re: Sorting result of function call
in thread Sorting result of function call

It's a bit ambiguous actually - should "sort subname" be interpreted as "using this sub as the sort comparison routine, sort the empty list" or "call this sub in list context and sort the results with the default sort comparator".

Maybe I'm misunderstanding you here, but "sort subname" is my first testcase and it neither behaves as your first alternative nor as your second!

[jbert]

Yes, I'd expect "sort subname" to mean "sort the empty list with the comparison func subname" - because "sort bareword LIST" means sort the (possibly empty) list with bareword as a comparison func.

And I'd expect "sort subname()" to mean "invoke subname to get a list, to sort with the default comparator" - because I interpret "subname()" to always mean "invoke subname".

So I'd expect your first two examples to have different behaviour (but not the behaviour we get).

But I'm not sure my expectations are in line with "documented reality", so I'm loath to say there definitely is a bug.

I'm hoping to learn something in this thread :-)

[ysth]

There's no way for perl to perfectly satisfy here: sort subname LIST is clearly documented as using subname as the comparator in sorting LIST, and making the the optional whitespace before the '(' around a list become required would be unfortunate. But that leads to sort subname() not being interpreted as you intended. If you can train yourself to always use & on a sub call producing a list to be sorted, you'll be well off.