I was making great progress with my first attempt using Perl but have come across an uninitialized value problem.

I've distilled the issue down to the following code. I define a hash with 1 pair, ask the user to input a number. Then the hash is undef.

I'm using a fresh strawberry install and run it from the cmd line in Win 7 using 'perl filename.pl'

#! /usr/bin/perl
use feature ':5.10';
use strict;
use warnings;

#define a hash
my %p = ("1","Rekjavik");

#check it's there (returns "Rekjavik")
say $p{1};

#ask for input from user (user inputs the number 1)
my $t = <>;

#the hash has disappeared! (returns undef)
say $p{$t};

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In reply to Hash becomes uninitalized without warning... with warning by sendrahiok

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