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
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inspect.ismodule(object): 是否为模块
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inspect.isclass(object):是否为类
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inspect.ismethod(object):是否为方法(bound method written in python)
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inspect.isfunction(object):是否为函数(python function, including lambda expression)
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inspect.isgeneratorfunction(object):是否为python生成器函数
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inspect.isgenerator(object):是否为生成器
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inspect.istraceback(object): 是否为traceback
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inspect.isframe(object):是否为frame
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inspect.iscode(object):是否为code
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inspect.isbuiltin(object):是否为built-in函数或built-in方法
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inspect.isroutine(object):是否为用户自定义或者built-in函数或方法
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inspect.isabstract(object):是否为抽象基类
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inspect.ismethoddescriptor(object):是否为方法标识符
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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
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inspect.isgetsetdescriptor(object):是否为getset descriptor
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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:
Type | Attribute | Description | Notes |
---|---|---|---|
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])