Perl, Python - リファレンスを使った実践的なテクニック(再帰的なディレクトリ表示ルーチン(インデント付き))

続・初めてのPerl 改訂版
Randal L. Schwartz
brian d foy, Tom Phoenix 著

開発環境

• OS X Lion - Apple(OS)
• BBEdit - Bare Bones Software, Inc., Emacs(Text Editor)
• プログラミング言語: Perl

『続・初めてのPerl 改訂版』(Randal L. Schwartz, brian d foy, Tom Phoenix 著、伊藤 直也、田中 慎司、吉川 英興 監訳、株式会社ロングテール/長尾 高弘 訳、オライリー・ジャパン、2006年、ISBN4-87311-305-9)の9章(リファレンスを使った実践的なテクニック)の9.9(練習問題)4を解いてみる。

その他参考書籍

• プログラミングPerl〈VOLUME1〉
• プログラミングPerl〈VOLUME2〉
• Perlクックブック〈VOLUME1〉
• Perlクックブック〈VOLUME2〉

4.

コード(BBEdit)

sample.pl

#!/usr/bin/env perl
use strict;
use warnings;
use 5.016;
use utf8;
binmode STDOUT, ':utf8';
binmode STDIN, ':utf8';
binmode STDERR, ':utf8';
use File::Basename;

sub data_for_path {
    my $path = shift;
    if (-f $path or -l $path) {
        return undef;
    }
    if (-d $path) {
        my %directory;
        opendir PATH, $path or die "Cannot opendir $path: $1";
        my @names = readdir PATH;
        closedir PATH;
        for my $name (@names) {
            next if $name eq '.' or $name eq '..';
            $directory{$name} = data_for_path("$path/$name");
        }
        return \%directory;
    }
    warn "$path is neither a file nor a directory\n";
    return undef;
}

sub dump_data_for_path {
    my $pre = shift;
    my $path = shift;
    my $data = shift;
    print "  " x $pre . $path;
    if (not defined $data) {
        print "\n";
        return;
    }
    
    my %directory = %$data;
    
    if (%directory) {
        print ", with contents:\n";
        for (sort keys %directory) {
            $pre += 1;
            dump_data_for_path($pre, $_, $directory{$_});
            $pre -= 1;
        }
    } else {
        print ", an empty directory\n";
    }
}

dump_data_for_path(0, ".", data_for_path('.'));

入出力結果(Terminal)

$ ./sample.pl
., with contents:
  .DS_Store
  .out
  Gilligan:
  Ginger:
  Lovey:
  MaryAnn:
  MonkeyMan:
  Oogaboogoo, with contents:
    __pycache__, with contents:
      date.cpython-33.pyc
    date.pm
    date.py
  Professor:
  Skipper:
  Thurston:
  __pycache__, with contents:
    sample.cpython-32.pyc
    sample.cpython-33.pyc
  barney
  betty
  coconet.dat
  coconet_total.dat
  coconet_total_2.dat
  date.txt
  distribute-0.6.34.tar.gz
  empty_folder, an empty directory
  fred
  hello_world.pl
  html
  link_test
  ln.txt
  ln1.txt
  log
  log.dat
  log_file.txt
  ls.out
  numbers
  perl_kamimura_blog
  perl_kamimura_blog.html
  perl_program1
  result
  sample, with contents:
    .DS_Store
    sample_folder, an empty directory
    sample_folder copy, an empty directory
    sample_folder copy 2, an empty directory
    sample_folder copy 3, an empty directory
    sample_folder copy 4, an empty directory
  sample.pl
  sample.py
  sample.txt
  sample_folder, with contents:
    .DS_Store
    sample1.bak
    test
  sample_text
  some_file
  some_folder, with contents:
    .DS_Store
    ln.txt
    mv1.txt
    sample.pl
    some_file
    some_file1
    some_file2
    symlink.txt
  sortable_hash
  standings.db
  test.out
  test.py
  test.txt
  test.txt.out
  test_folder, with contents:
    .DS_Store
    sample, with contents:
      sample.txt
  test_link
  tmp.txt
  tmp1.txt
  tmp2.txt
  total_bytes.dat
  untitled text 2.txt
$

ちなみにpython3.3の場合。

コード(BBEdit)

sample.py

#!/usr/bin/env python3.3
## Copyright (C) 2013 by kamimura
#-*- coding: utf-8 -*-

import os
import glob

def dataForPath(path):
    if os.path.isfile(path) or os.path.islink(path):
        return
    if os.path.isdir(path):
        directory = {}
        names = glob.glob('{0}{1}*'.format(path, os.path.sep))
        for name in names:
            directory[name] = dataForPath(path + os.path.sep + name)
        return directory

def dumpDataForPath(pre, path, data):
    print("  " * pre + os.path.basename(path), end="")
    if data == None:
        print()
        return
    
    if data:        
        print(", with contents:")
        for key in sorted(data.keys()):
            pre += 1
            dumpDataForPath(pre, key, data[key])
            pre -= 1
    else:
        print(", an empty directory")

dumpDataForPath(0, '.', dataForPath('.'))

入出力結果(Terminal)

$ ./sample.py
., with contents:
  Gilligan:
  Ginger:
  Lovey:
  MaryAnn:
  MonkeyMan:
  Oogaboogoo, with contents:
    __pycache__
    date.pm
    date.py
  Professor:
  Skipper:
  Thurston:
  __pycache__, with contents:
    sample.cpython-32.pyc
    sample.cpython-33.pyc
  barney
  betty
  coconet.dat
  coconet_total.dat
  coconet_total_2.dat
  date.txt
  distribute-0.6.34.tar.gz
  empty_folder, an empty directory
  fred
  hello_world.pl
  html
  link_test
  ln.txt
  ln1.txt
  log
  log.dat
  log_file.txt
  ls.out
  numbers
  perl_kamimura_blog
  perl_kamimura_blog.html
  perl_program1
  result
  sample, with contents:
    sample_folder
    sample_folder copy
    sample_folder copy 2
    sample_folder copy 3
    sample_folder copy 4
  sample.pl
  sample.py
  sample.txt
  sample_folder, with contents:
    sample1.bak
    test
  sample_text
  some_file
  some_folder, with contents:
    ln.txt
    mv1.txt
    sample.pl
    some_file
    some_file1
    some_file2
    symlink.txt
  sortable_hash
  standings.db
  test.out
  test.py
  test.txt
  test.txt.out
  test_folder, with contents:
    sample
  test_link
  tmp.txt
  tmp1.txt
  tmp2.txt
  total_bytes.dat
  untitled text 2.txt
$