perl - create file name from column names

Question

I am new to Perl and I would like to create the name of the output file based on the column names present in the input file. Say that my input file header is the following:

#identifier    (%)composition

and I would like my output file name to be identifier_composition. These identifiers and compositions can be a sequence of alphanumeric characters such as #E2FAR4 for identifier or (%)MhDE4 for composition. For this example, the output file name should be E2FAR4_MhDE4. So far, I am able to get the identifier but not the composition. This is what I have tried as code:

if ($line =~ /^#\s*(\S+)\t\(%)s*(\S+)/){
    my $ID = $1;
    my $comp = $2;
    my $out_file = "${ID}_${comp}"
}

but I get the identifier also as the second argument. Any help would be appreciated.

Answer 1

Use below regex

^#\s*(\S+)\t\(%\)(\S+)

Demo

Example code:

#!/usr/bin/perl
use strict;
use warnings;
while(<DATA>){
    my $line = $_;
    chomp $line;
    if ($line =~ /^#\s*(\S+)\t\(%\)(\S+)/){
        my $ID = $1;
        my $comp = $2;
        my $out_file = "${ID}_${comp}";
        print "Filename: $out_file";
    }
}

__DATA__
#identifier (%)composition

Output:

Filename: identifier_composition