Good Afternoon Monks,
My question is not so much a question but an explanation is needed concerning the following code: 

#!/usr/bin/perl -w

use strict;
use warnings;

my $file = "data.txt";       

local $^I = ".bak";
local @ARGV = ($file);
while (<>) {
chomp;
my @field = split(':');
if ($field[1] =~ s/E/L/g) {
print "$field[0]:$field[1]\n";
} elsif ($field[1] =~ s/L/E/g) {
print "$field[0]:$field[1]\n";
} else {
print "$_\n";
}
}
unlink("$file.bak");

print "UPDATED!!";

sleep 5;
exit();

__DATA__
1:E
2:L
3:L

[download]

As you can see once the code is executed it does change the L to an E and vice versa. My question is why is it saying use of uninitialized value in $field1 in substitution ring when in fact $field1 does have a value? Thanks for the clarification.

In reply to Uninitialized Value by PilotinControl

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