http://qs1969.pair.com?node_id=460969


in reply to string comparison

You could just rejoin your strings after spliting and sorting and then compare them: 

#! perl -slw
use strict;

sub reorder {
    my $string = shift;
    return join ',', sort{ $a cmp $b } split ',', $string;
};;

my $string1 = '~cake,pastry';
my $string2 = 'pastry,~cake';
my $string3 = 'cake,pastry';

print "$_->[ 0 ] eq $_->[ 1 ]",
    reorder( $_->[ 0 ] ) eq reorder( $_->[ 1 ] )
        ? ' match '
        : ' dont match'
    for [ $string1, $string2 ],
        [ $string1, $string3 ],
        [ $string2, $string3 ];
__END__

[ 8:16:14.39] P:\test>junk2
~cake,pastry eq pastry,~cake match
~cake,pastry eq cake,pastry dont match
pastry,~cake eq cake,pastry dont match

[download]

Not hugely efficient, but probably not too bad if there are only a few elements in your strings.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
The "good enough" maybe good enough for the now, and perfection maybe unobtainable, but that should not preclude us from striving for perfection, when time, circumstance or desire allow.

Replies are listed 'Best First'.
Re^2: string comparison
by reasonablekeith (Deacon) on May 27, 2005 at 08:51 UTC
    Seems like an overly complicated example. Isn't it just as simple as... ? 
    my $string1 = '~cake,pastry';
my $string2 = 'pastry,~caske';

if (sort_text($string1) eq sort_text($string2)) {
    print "match\n";
}
sub sort_text { join(',', sort split(/,/, $_[0]) ) }

    [download]
    ---
    my name's not Keith, and I'm not reasonable.
[reply]
[d/l]
      Extending this logic a bit, and using <DATA> to read in the test data: 
      use strict;
use warnings;
my ($first_line, $current_line);
while (<DATA>) {    
    chomp; # get rid of newline
    # get the first line sorted
    if ($. == 1) {
        $first_line = join ",", sort( split /,/,);    
    } else { #die if doesn't match the first line sorted.
        $current_line = join ",", sort( split /,/,);
        die "$_ didn't match first line" unless $current_line eq $firs
+t_line;
    }


}
__DATA__
~cake,pastry,donuts,meringue
pastry,~cake,meringue,donuts
meringue,
donuts,pastry,~cake,meringue

      [download]
      This dies on the third line, as it should.
[reply]
[d/l]

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