Yes, probably it was not well-written. Imagine this script:
use strict;
use warnings;

my %res;
my $id='';
my $rest='';
my $seq='';
while (<DATA>) 
{
    chomp;
    if($_=~/^>(.*?)\|(.*)/)
    {
        $id=$1;
        $rest=$2;
        $seq=<DATA>;
        chomp $seq;
    }
}

_DATA_
>id1|Q51487|P-474-4|86-98,113-126,297-310,322-335
CSLIPDYQRPEAPVAAAYPQGQAYGQNTGAAAVPAADIGWREFFRDPQLQQLIGVALE
>id2|Q51487|P-474-4|86-98,113-126,297-310,322-335
CSLIPDYQRPEAPVAAAYPQGQAYGQNTGAAAVPAADIGWREFFRDPQLQQLIGVALE
>id3|Q51487|P-474-4|86-98,113-126,297-310,322-335
CSLIPDYQRPEAPVAAAYPQGQAYGQNTGAAAVPAADIGWREFFRDPQLQQLIGVALE

[download]

and I want to go to:
>id1|id2|id3|Q51487|P-474-4|86-98,113-126,297-310,322-335
CSLIPDYQRPEAPVAAAYPQGQAYGQNTGAAAVPAADIGWREFFRDPQLQQLIGVALE

[download]

And I wonder if I can use some of Perl's data structures, or the map command?

In reply to Re^2: How do I use the map command for this? by Anonymous Monk
in thread How do I use the map command for this? by Anonymous Monk

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