ch19.020_best

来自「Perl Best Practices the source code」· 020_BEST 代码 · 共 33 行

##############################################################################
##   Code fragment (Recommended) from Chapter 19 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;




my @raw_requests = (1..5, 1..4, 1..3, 1..2);

sub unique {
    my %seen;                        # Keys track values already seen
    return grep {!$seen{$_}++} @_;   # Keep only those not yet seen
}
 
# and later...
 
my @requests = unique(@raw_requests);

use Data::Dumper 'Dumper';
warn Dumper [ @requests ];