Python Tutorial // Comee

Built-in objects preview

Object type	Example literals/creation
Numbers	`1234`, `3.1415`, `3+4j`, `Decimal`, `Fraction`
Strings	`'spam'`, `"guido's"`, `b'a\xolc'`
Lists	`[1,[2,'three'],4]`
Dictionaries	`{'foo':'spam','taste':'yum'}`, `dict(hours=10)`
Tuples	`(1,'spam',4,'U')`, `tuple('spam')`
Files	`myfile=open('eggs','r')`, `_myfile=open(r'C:\ham.bin','wb')`
Sets	`set('abc')`, `{'a','b','c'}`
Other core types	Booleans, types, None
Program unit types	Functions, modules, classes
Implementation-related types	Complied code, stack tracebacks

列表是一个序列，其元素是有序的，字典更像是映射（key -> value），元组根本上就是一个不可以改变的列表，集合是唯一的可变的对象的无序集合。

寻求帮助

使用 dir 函数可以查看对象的所有属性（方法也是对象的属性），使用 help 函数可以查看具体的方法：

>>> S = '123'
>>> dir(S)
['__add__', '__class__', '__contains__', '__delattr__', '__dir__', '__doc__',
 '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', 
 '__getnewargs__', '__gt__', '__hash__', '__init__', '__iter__', '__le__', 
 '__len__', '__lt__', '__mod__', '__mul__', '__ne__', '__new__', '__reduce__',
 '__reduce_ex__', '__repr__', '__rmod__', '__rmul__', '__setattr__', 
 '__sizeof__', '__str__', '__subclasshook__', 'capitalize', 'casefold', 
 'center', 'count', 'encode', 'endswith', 'expandtabs', 'find', 'format',
 'format_map', 'index', 'isalnum', 'isalpha', 'isdecimal', 'isdigit', 
 'isidentifier', 'islower', 'isnumeric', 'isprintable', 'isspace', 'istitle', 
 'isupper', 'join', 'ljust', 'lower', 'lstrip', 'maketrans', 'partition', 
 'replace', 'rfind', 'rindex', 'rjust', 'rpartition', 'rsplit', 'rstrip', 
 'split', 'splitlines', 'startswith', 'strip', 'swapcase', 'title', 'translate', 
 'upper', 'zfill']
>>> help(S.replace)
Help on built-in function replace:

replace(...) method of builtins.str instance
    S.replace(old, new[, count]) -> str

    Return a copy of S with all occurrences of substring
    old replaced by new.  If the optional argument count is
    given, only the first count occurrences are replaced.

>>>

Python 编码规范

使用 pylint 进行代码检查

在 Windows 下安装 pylint ：

1	pip install pylint

编写批处理测试脚本 pylint.bat ，方便测试：

@echo off

set python_file=%~1
for /f "tokens=2,*" %%i in ('reg query "HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders" /v "Desktop"') do set desktop=%%j 
set output_dir=%desktop:~0,-1%\pylint_log.txt
call pylint %python_file% > %output_dir%

:pylint
::---------pylint结果输出到文件
::---------参数%1为python文件
::---------调用：call :pylint test.py
::@echo off
set python_f = %~1
if not defined python_f goto :eof
pylint %python_f%
goto :eof

pylint.bat 使用：

C:\Users\Leo>C:\Users\Leo\Desktop\pylint.bat F:\eclipse\workspaces\20140719\OOMMonitor\OOMMonitor.py
No config file found, using default configuration

C:\Users\Leo>

输出结果在桌面的 pylint_log.txt 文件中，内容大致如下：

************* Module OOMMonitor
R: 98, 0: Too many instance attributes (16/7) (too-many-instance-attributes)
E:125,38: Module 'win32event' has no 'CreateEvent' member (no-member)
C:147, 4: Invalid method name "SvcStop" (invalid-name)
E:152,46: Module 'win32service' has no 'SERVICE_STOP_PENDING' member (no-member)
E:154,19: Module 'win32event' has no 'SetEvent' member (no-member)
C:156, 4: Invalid method name "SvcDoRun" (invalid-name)
W:164,15: Catching too general exception Exception (broad-except)
E:171,19: Module 'win32event' has no 'WaitForSingleObject' member (no-member)
E:171,68: Module 'win32event' has no 'INFINITE' member (no-member)
W:203,26: Unused variable 'dirs' (unused-variable)
W:232,15: Catching too general exception Exception (broad-except)
W:281,23: Catching too general exception Exception (broad-except)
W:465,19: Catching too general exception Exception (broad-except)



Report

======

296 statements analysed.



Statistics by type

------------------


+---------+-------+-----------+-----------+------------+---------+
|type     |number |old number |difference |%documented |%badname |
+=========+=======+===========+===========+============+=========+
|module   |1      |1          |=          |100.00      |0.00     |
+---------+-------+-----------+-----------+------------+---------+
|class    |1      |1          |=          |100.00      |0.00     |
+---------+-------+-----------+-----------+------------+---------+
|method   |15     |15         |=          |100.00      |13.33    |
+---------+-------+-----------+-----------+------------+---------+
|function |5      |5          |=          |100.00      |0.00     |
+---------+-------+-----------+-----------+------------+---------+






External dependencies

---------------------

::


    bs4 (OOMMonitor)

    win32event (OOMMonitor)

    win32service (OOMMonitor)

    win32serviceutil (OOMMonitor)







Raw metrics

-----------


+----------+-------+------+---------+-----------+
|type      |number |%     |previous |difference |
+==========+=======+======+=========+===========+
|code      |303    |68.86 |303      |=          |
+----------+-------+------+---------+-----------+
|docstring |92     |20.91 |92       |=          |
+----------+-------+------+---------+-----------+
|comment   |9      |2.05  |9        |=          |
+----------+-------+------+---------+-----------+
|empty     |36     |8.18  |36       |=          |
+----------+-------+------+---------+-----------+






Duplication

-----------


+-------------------------+------+---------+-----------+
|                         |now   |previous |difference |
+=========================+======+=========+===========+
|nb duplicated lines      |0     |0        |=          |
+-------------------------+------+---------+-----------+
|percent duplicated lines |0.000 |0.000    |=          |
+-------------------------+------+---------+-----------+






Messages by category

--------------------


+-----------+-------+---------+-----------+
|type       |number |previous |difference |
+===========+=======+=========+===========+
|convention |2      |2        |=          |
+-----------+-------+---------+-----------+
|refactor   |1      |1        |=          |
+-----------+-------+---------+-----------+
|warning    |5      |5        |=          |
+-----------+-------+---------+-----------+
|error      |5      |5        |=          |
+-----------+-------+---------+-----------+






Messages

--------


+-----------------------------+------------+
|message id                   |occurrences |
+=============================+============+
|no-member                    |5           |
+-----------------------------+------------+
|broad-except                 |4           |
+-----------------------------+------------+
|invalid-name                 |2           |
+-----------------------------+------------+
|unused-variable              |1           |
+-----------------------------+------------+
|too-many-instance-attributes |1           |
+-----------------------------+------------+






Global evaluation

-----------------

Your code has been rated at 8.89/10 (previous run: 8.89/10, +0.00)