#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;

my %clone_hash;
while (<DATA>)
{
    chomp;
    my @fields = split /\t/;         
    my ($gene_symbol, $esc_qc) = ($fields[0], $fields[1]);
    $clone_hash{$gene_symbol} = $esc_qc;
    my $grade = ($esc_qc =~ /^pass[1-3]$/) ? 'good' : 'bad';
    $clone_hash{$key}{$grade}++;
}
print Dumper(\%clone_hash);

_DATA_
4933402D24Rik    fail
4933402D24Rik    fail
4933402D24Rik    fail
4933402D24Rik    fail
4933402D24Rik    fail
4933402D24Rik    fail
4933402D24Rik    fail
4933402D24Rik    pass1
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When I run this I get an error message stating that a
bareword is found where an operator is expected near
"4933402D24Rik"(missing operator before "D24Rik"),
what does this mean?