ch06.073_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;

my @file_paths = qw(
    dev/null
    dev/null/nuller
    localized
    etc/etc/ad/nauseam
    dev/some
);
my @dir_paths;

# Track directory paths to ensure uniqueness...
my %seen_dir;
 
FILE_PATH:
for my $file (@file_paths) {
    # Default to current directory...
    my $dir_path = './';
 
    # Capture and remove any actual directory path and use it as the path...
    if ($file =~ s{ \A (.*/) }{}xms) {
        $dir_path = $1;
    }
 
    # Reject repeated directory paths...
    next FILE_PATH if $seen_dir{$dir_path}++;
 
    # Record the extracted path...
    push @dir_paths, $dir_path;
} 


use Data::Dumper 'Dumper';
warn Dumper [ @dir_paths ];
warn Dumper [ @file_paths ];