in reply to Getting values from a Hash from user input

Another way is to use Perl's defined-or operator (//):

use strict;
use warnings;

my %words = ( 'hello' => 'world' );

print 'type a word: ';
chomp( my $inData = <> );

print $words{$inData} // "Key '$inData' doesn't exist.\n";

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If the key's defined, it's associated value will be printed, otherwise the 'default' string will be printed.

Hope this helps!

Edit: //= -> //. Thank you, Eily.

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Re^2: Getting values from a Hash from user input
by Eily (Monsignor) on Nov 21, 2013 at 21:33 UTC

    The defined-or operator is just //. $lvalue //= "value"; actually means $lvalue = "value" unless defined $lvalue;. This means that you actually write "Key '$inData' doesn't exist.\n" in the hash : 

    use Data::Dumper;

my %words = ( 'hello' => 'world' );

print 'type a word: ';
chomp( my $inData = <> );
print $words{$inData} //= "Key '$inData' doesn't exist.\n";

print Dumper \%words;

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    type a word: Bonjour
Key 'Bonjour' doesn't exist.
$VAR1 = {
          'hello' => 'world',
          'Bonjour' => 'Key \'Bonjour\' doesn\'t exist.
'
        };

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    You meant print $words{$inData} // "Key '$inData' doesn't exist.\n"; which works fine as long as undef isn't a valid value.

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[d/l]
[select]

      Thanks for this catch! Corrected...

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        Thanks for help guys

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