in reply to "Intelligent" array joining

I think the OP wants something like this: 
#!/your/perl/here

use strict;
use warnings;

my @array1 = qw(dog cat rat mouse);
my @array2 = qw(dog rat mouse bird);
my @array3 = qw(cat rat fish mouse);

my %seen;
my @collection;

foreach my $item ( @array1, @array2, @array3 )
{
    unless ( exists( $seen{$item} ) )
    {
        push @collection, $item;
        $seen{$item}++;
    }
}

print "@collection\n";

__END__

[download]
Which gives: 
dog cat rat mouse bird fish

[download]
I'll leave it to OMAR to come up with an obfuscated compact form.

-QM
--
Quantum Mechanics: The dreams stuff is made of

Replies are listed 'Best First'.
Re: Re: "Intelligent" array joining
by dragonchild (Archbishop) on Feb 06, 2004 at 03:22 UTC
    Doesn't work. Try the following test: 
    my @array1 = qw(dog cat rat mouse);
my @array2 = qw(dog rat mouse bird);
my @array3 = qw(cat rat fish mouse);

my %seen;
my @collection;

foreach my $item ( @array1, @array2, @array3 )
{
    unless ( exists( $seen{$item} ) )
    {
        push @collection, $item;
        $seen{$item}++;
    }
}

print "@collection\n";

@collection = ();
%seen = ();
foreach my $item ( @array2, @array1, @array3 )
{
    unless ( exists( $seen{$item} ) )
    {
        push @collection, $item;
        $seen{$item}++;
    }
}

print "@collection\n";

__END__

    [download]

    Prints: 

    dog cat rat mouse bird fish
dog rat mouse bird cat fish

    [download]

    Theoretically, it should always give the same order, no matter what order the initial arrays are in.

    ------
    We are the carpenters and bricklayers of the Information Age.

    Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.

[reply]
[d/l]
[select]
      Theoretically, it should always give the same order, no matter what order the initial arrays are in.
      Ah, I missed that in the specification. I suppose if the OP could have stated the problem better, s/he might have known where to find it in the first place, no? ;)

      -QM
      --
      Quantum Mechanics: The dreams stuff is made of

[reply]

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