I've never really understood anonymous subroutines, or inline subroutines, which is what you usually do with sort. But I imagine I should create a named subroutine that returns 1,0 or -1 according to my own criteria as listed above, am I right?

You are right there. Create a sub that when given any 2 atoms, returns 1 if the first is larger than the second, 0 if they are equal, or -1 if the first is smaller than the second, for whatever definition of larger, equal and smaller you are using. (Note: use $a and $b for the first and second atom given to the sub, as in my example below).

As for the inline/anonymous subs for sort, they are fairly simple. For example if you had: 

sub foo {
   return $a cmp $b
}
my @sorted = sort foo @unsorted;

[download]
You could replace it with: 
my @sorted = sort { return $a cmp $b } @unsorted;

[download]
or even: 
my @sorted = sort { $a cmp $b } @unsorted;

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as a sub implicitly returns the value of the last statement evaluated.

That's pretty much all there is to using an anonymous sub with sort. Of course, if you are using the same sort in more than 1 place, it would be better to make a named sub, that way you only have to change 1 thing if you decide to sort differently later.

In reply to Re: sorting according to greek alphabet in roman letters by Paladin
in thread sorting according to greek alphabet in roman letters by seaver

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