Reorder list.pl

#!/usr/bin/perl
#reorders the list

use warnings;
use strict;

sub feature_sort;

# read in file
# if it pattern matches 
open( THE_CPP, "FeatureNames.cpp" ) or die "wtf?\n";

my %line_hash;

while( <THE_CPP> ) {
	if( $_ =~ /^\told_features_.*= "(.*)";/ )
	{
		push @{ $line_hash{ $1 } }, $_;
	}
}
close THE_CPP;

open ( OUT, '>', "sorted_old_feat_names.txt") or die "aye carumba!\n";

my $line_count = 0;
foreach my $featurename ( sort feature_sort keys %line_hash ) {
	foreach my $old_featurename ( sort @{ $line_hash{ $featurename } } ) {
		++$line_count;
		#print $line_count . ".) " . $old_featurename;
		print OUT $old_featurename;
	}
}
close OUT;


sub feature_sort {

	my ($a_stem, $a_bin, $b_stem, $b_bin );

	if( $a =~ /(.*) \[(\d+)\]/ ) {
		$a_stem = $1;
		$a_bin = $2;
	}
	if( $b =~ /(.*) \[(\d+)\]/ ) {
		$b_stem = $1;
		$b_bin = $2;
	}

	if ( $a_stem && $a_bin && $b_stem && $b_bin ) {
		if ($a_stem ne $b_stem ) { return $a cmp $b } 
		else { return $a_bin <=> $b_bin; } 
	}
	else {
		return $a cmp $b;
	}
}