You can put the uc or lc inside the code block of the sort function as Roger has demonstrated, and that's a perfectly legitimate solution. But there's a more efficient way; one that doesn't require a set of calls to lc for each sort comparison. The more efficient way is known as the Schwartzian Transform: 

my @sorted = map { $_->[0] } sort { $a->[1] cmp $b->[1] }
             map { [ $_, uc $_ ] } @unsorted;

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The reason this method is often preferable is that the uc function is only called once per item being sorted, rather than each time that item is compared. Yes, there is some cost associated with the two map transforms, but that usually will be less than the cost of 'expensive' routines in the comparison function.


Dave

In reply to Re: noncase-sensitive sorting by davido
in thread noncase-sensitive sorting by texuser74

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