python--inspect模块

inspect模块主要提供了四种用处:

  1.对是否是模块、框架、函数进行类型检查

  2.获取源码

  3.获取类或者函数的参数信息

  4.解析堆栈

 

一、type and members

1. inspect.getmembers(object[, predicate])

第二个参数通常可以根据需要调用如下16个方法;

返回值为object的所有成员,以(name,value)对组成的列表

  1. inspect.ismodule(object): 是否为模块

  2. inspect.isclass(object):是否为类

  3. inspect.ismethod(object):是否为方法(bound method written in python)

  4. inspect.isfunction(object):是否为函数(python function, including lambda expression)

  5. inspect.isgeneratorfunction(object):是否为python生成器函数

  6. inspect.isgenerator(object):是否为生成器

  7. inspect.istraceback(object): 是否为traceback

  8. inspect.isframe(object):是否为frame

  9. inspect.iscode(object):是否为code

  10. inspect.isbuiltin(object):是否为built-in函数或built-in方法

  11. inspect.isroutine(object):是否为用户自定义或者built-in函数或方法

  12. inspect.isabstract(object):是否为抽象基类

  13. inspect.ismethoddescriptor(object):是否为方法标识符

  14. inspect.isdatadescriptor(object):是否为数字标识符,数字标识符有__get__ 和__set__属性; 通常也有__name__和__doc__属性

  15. inspect.isgetsetdescriptor(object):是否为getset descriptor

  16. inspect.ismemberdescriptor(object):是否为member descriptor

inspect的getmembers()方法可以获取对象(module、class、method等)的如下属性: 

TypeAttributeDescriptionNotes
module __doc__ documentation string  
  __file__ filename (missing for built-in modules)  
class __doc__ documentation string  
  __module__ name of module in which this class was defined  
method __doc__ documentation string  
  __name__ name with which this method was defined  
  im_class class object that asked for this method (1)
  im_func or __func__ function object containing implementation of method  
  im_self or __self__ instance to which this method is bound, or None  
function __doc__ documentation string  
  __name__ name with which this function was defined  
  func_code code object containing compiled function bytecode  
  func_defaults tuple of any default values for arguments  
  func_doc (same as __doc__)  
  func_globals global namespace in which this function was defined  
  func_name (same as __name__)  
generator __iter__ defined to support iteration over container  
  close raises new GeneratorExit exception inside the generator to terminate the iteration  
  gi_code code object  
  gi_frame frame object or possibly None once the generator has been exhausted  
  gi_running set to 1 when generator is executing, 0 otherwise  
  next return the next item from the container  
  send resumes the generator and “sends” a value that becomes the result of the current yield-expression  
  throw used to raise an exception inside the generator  
traceback tb_frame frame object at this level  
  tb_lasti index of last attempted instruction in bytecode  
  tb_lineno current line number in Python source code  
  tb_next next inner traceback object (called by this level)  
frame f_back next outer frame object (this frame’s caller)  
  f_builtins builtins namespace seen by this frame  
  f_code code object being executed in this frame  
  f_exc_traceback traceback if raised in this frame, or None  
  f_exc_type exception type if raised in this frame, or None  
  f_exc_value exception value if raised in this frame, or None  
  f_globals global namespace seen by this frame  
  f_lasti index of last attempted instruction in bytecode  
  f_lineno current line number in Python source code  
  f_locals local namespace seen by this frame  
  f_restricted 0 or 1 if frame is in restricted execution mode  
  f_trace tracing function for this frame, or None  
code co_argcount number of arguments (not including * or ** args)  
  co_code string of raw compiled bytecode  
  co_consts tuple of constants used in the bytecode  
  co_filename name of file in which this code object was created  
  co_firstlineno number of first line in Python source code  
  co_flags bitmap: 1=optimized | 2=newlocals | 4=*arg |8=**arg  
  co_lnotab encoded mapping of line numbers to bytecode indices  
  co_name name with which this code object was defined  
  co_names tuple of names of local variables  
  co_nlocals number of local variables  
  co_stacksize virtual machine stack space required  
  co_varnames tuple of names of arguments and local variables  
builtin __doc__ documentation string  
  __name__ original name of this function or method  
  __self__ instance to which a method is bound, or None  

 

2. inspect.getmoduleinfo(path): 返回一个命名元组<named tuple>(name, suffix, mode, module_type)

  name:模块名(不包括其所在的package)

      suffix:

      mode:open()方法的模式,如:'r', 'a'等

      module_type: 整数,代表了模块的类型

3. inspect.getmodulename(path):根据path返回模块名(不包括其所在的package)

 

二、Retrieving source code

1. inspect.getdoc(object): 获取object的documentation信息

2. inspect.getcomments(object)

3. inspect.getfile(object): 返回对象的文件名

4. inspect.getmodule(object):返回object所属的模块名

5. inspect.getsourcefile(object): 返回object的python源文件名;object不能使built-in的module, class, mothod

6. inspect.getsourcelines(object):返回object的python源文件代码的内容,行号+代码行

7. inspect.getsource(object):以string形式返回object的源代码

8. inspect.cleandoc(doc):

 

三、class and functions

1. inspect.getclasstree(classes[, unique])

2. inspect.getargspec(func)

3. inspect.getargvalues(frame)

4. inspect.formatargspec(args[, varargs, varkw, defaults, formatarg, formatvarargs, formatvarkw, formatvalue, join])

5. inspect.formatargvalues(args[, varargs, varkw, locals, formatarg, formatvarargs, formatvarkw, formatvalue, join])

6. inspect.getmro(cls): 元组形式返回cls类的基类(包括cls类),以method resolution顺序;通常cls类为元素的第一个元素

7. inspect.getcallargs(func[, *args][, **kwds]):将args和kwds参数到绑定到为func的参数名;对bound方法,也绑定第一个参数(通常为self)到相应的实例;返回字典,对应参数名及其值;

>>> from inspect import getcallargs
>>> def f(a, b=1, *pos, **named):
...     pass
>>> getcallargs(f, 1, 2, 3)
{'a': 1, 'named': {}, 'b': 2, 'pos': (3,)}
>>> getcallargs(f, a=2, x=4)
{'a': 2, 'named': {'x': 4}, 'b': 1, 'pos': ()}
>>> getcallargs(f)
Traceback (most recent call last):
...
TypeError: f() takes at least 1 argument (0 given)

四、The interpreter stack

1. inspect.getframeinfo(frame[, context])

2. inspect.getouterframes(frame[, context])

3. inspect.getinnerframes(traceback[, context])

4. inspect.currentframe()

5. inspect.stack([context])

6. inspect.trace([context])

 

posted @ 2018-04-18 16:08  姚红  阅读(31688)  评论(0编辑  收藏  举报