ch06.075_best

Perl Best Practices the source code

##############################################################################
##   Code fragment (Recommended) from Chapter 6 of "Perl Best Practices"    ##
##     Copyright (c) O'Reilly & Associates, 2005. All Rights Reserved.      ##
##  See: http://www.oreilly.com/pub/a/oreilly/ask_tim/2001/codepolicy.html  ##
##############################################################################


# Standard modules...
use strict;
use warnings;
use IO::Prompt;
use Carp;
use English qw( -no_match_vars );
use Data::Alias;
use Readonly;

Readonly my $EMPTY_STR => q{};

my %num_for = (
#   English       Fran鏰is        Fran鏰ise
   'zero' => 0,   'z閞o' => 0,
    'one' => 1,     'un' => 1,    'une' => 1,
    'two' => 2,   'deux' => 2,
  'three' => 3,  'trois' => 3,
   'four' => 4, 'quatre' => 4,	
   'five' => 5,   'cinq' => 5,
    'six' => 6,	  'sixe' => 6,
  'seven' => 7,	  'sept' => 7,
  'eight' => 8,	  'huit' => 8,
   'nine' => 9,   'neuf' => 9,
);
 
sub words_to_num {
    my ($words) = @_;
    
    # Treat each sequence of non-whitespace as a word...
    my @words = split /\s+/, $words;
 
    # Translate each word to the appropriate number...
    my $num = $EMPTY_STR;
    for my $word (@words) {
        my $digit = $num_for{lc $word};
        if (defined $digit) {
             $num .= $digit;
        }
    }
 
    return $num;
}
 
# and later...
 
print words_to_num('one zero eight neuf');    # prints: 1089