Another way (slurping the entire file into 1 string). 
#!/usr/bin/perl
use strict;
use warnings;

my $file = <<EOF;
TCONS_00000047 XLOC_000039
TCONS_00000718 XLOC_000456 
TCONS_00000938 XLOC_000610
TCONS_00004086 XLOC_002872
TCONS_00004252 XLOC_003003
TCONS_00004975 XLOC_003624
TCONS_00004976 XLOC_003624
TCONS_00005492 XLOC_004020
EOF

open my $fh, "<", \$file;

my $slurp; do {local $/; $slurp = <$fh>};

my %hash = split ' ', $slurp;

use Data::Dumper; print Dumper \%hash;

[download]
$VAR1 = {
          'TCONS_00004086' => 'XLOC_002872',
          'TCONS_00004976' => 'XLOC_003624',
          'TCONS_00004975' => 'XLOC_003624',
          'TCONS_00000718' => 'XLOC_000456',
          'TCONS_00000047' => 'XLOC_000039',
          'TCONS_00005492' => 'XLOC_004020',
          'TCONS_00000938' => 'XLOC_000610',
          'TCONS_00004252' => 'XLOC_003003'
        };

[download]

In reply to Re: create hashes using regex by Cristoforo
in thread create hashes using regex by bingalee

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