Python - Getting Started(Modules)

Learning Python
(Oreilly & Associates Inc)
Mark Lutz (著)

開発環境

• OS X Mavericks - Apple(OS)
• Emacs (CUI)、BBEdit - Bare Bones Software, Inc. (GUI) (Text Editor)
• Python (プログラミング言語)

Learning Python (Mark Lutz (著)、Oreilly & Associates Inc)のPart Ⅰ.(Getting Started)、Test Your Knowledge: Part I Exercises、3. (Modules)を解いてみる。

その他参考書籍

• Pythonチュートリアル 第2版
• Python クックブック 第2版

3. (Modules)

コード(BBEdit)

module1.py

print('Hello module world!')

入出力結果(Terminal)

$ python3
Python 3.3.3 (default, Dec  2 2013, 01:40:21) 
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.2.79)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import module1
Hello module world!
>>> 
[1]+  Stopped                 python3.3
$ ls
__pycache__ blog.html module1.py tmp
$ ls -F
__pycache__/ blog.html module1.py tmp/
$ mv module1.py tmp
$ ls
__pycache__ blog.html tmp
$ fg
python3.3
import imp
import imp
>>> imp.reload(module1)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/imp.py", line 276, in reload
    module.__loader__.load_module(name)
  File "<frozen importlib._bootstrap>", line 584, in _check_name_wrapper
  File "<frozen importlib._bootstrap>", line 1022, in load_module
  File "<frozen importlib._bootstrap>", line 1003, in load_module
  File "<frozen importlib._bootstrap>", line 560, in module_for_loader_wrapper
  File "<frozen importlib._bootstrap>", line 853, in _load_module
  File "<frozen importlib._bootstrap>", line 948, in get_code
  File "<frozen importlib._bootstrap>", line 1041, in path_stats
FileNotFoundError: [Errno 2] No such file or directory: './module1.py'
>>> quit()
$ ls
__pycache__ blog.html tmp
$ rm -rf __pycache__/
$ mv tmp/module1.py .
$ ls
blog.html module1.py tmp
$ python
Python 2.7.6 (default, Nov 18 2013, 15:12:51) 
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.2.79)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import module1
Hello module world!
>>> 
[1]+  Stopped                 python
$ ls
blog.html module1.py module1.pyc tmp
$ mv module1.py tmp
$ fg
python
reload(module1)
reload(module1)
Hello module world!
<module 'module1' from 'module1.pyc'>
>>> quit()
$ ls
blog.html module1.pyc tmp
$ python3
Python 3.3.3 (default, Dec  2 2013, 01:40:21) 
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.2.79)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import module1
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: bad magic number in 'module1': b'\x03\xf3\r\n'
>>> quit()
$

python2.xとpython3.xでモジュールのリロードについて、方法(impモジュール、reload関数等)や挙動(作成するファイル__pycache__/(ディレクトリ)、module1.pyc)が違うことに注意。