++ for seeing that you don't need a regex to get hold of the date part.

But why do you transform the date into a Date::Simple object in order to sort it? A date in the yyyymmdd format can be sorted numerically without any further ado.

And of course, this kind of thing just screams for the Schwartzian Transform: 

use strict;
use warnings;
use Data::Dumper;

my @xml_files = map { $_->[0] }
                sort { $a->[1] <=> $b->[1] }
                map { [$_, (split /_/, $_)[1]] }
                <DATA>;

print Dumper \@xml_files;

__DATA__
123_20070303_REFNUM.xml
123_20071225_REFNUM.xml
123_20080101_REFNUM.xml
923_20070227_REFNUM.xml

[download]

If there are only a few files to be sorted, it is of course overkill, but once the number of files increases the fact that you only have to do the split once for each file pays of.

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

In reply to Re^2: The Dates Sorting! by CountZero
in thread The Dates Sorting! by Anonymous Monk

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