python强大的自省功能

ustbwang

　　Python语言是一种弱类型的动态语言，很多时候使用过程中不知道某个对象或者变量的类型，但是由于其具备有强大的自省功能，因此可以依据其自省来获取该对象或者变量的很多信息
　　代码：

#!/usr/bin/env python
def interrogate(var):
print 'ID: ', id(var)
print 'Type: ', type(var)
print 'Value: ', repr(var)
if hasattr(var,'__name__'):
print 'NAME: ', var.__name__
if hasattr(var,'__class__'):
print 'CLASS: ', var.__class__
if hasattr(var,'__doc__'):
print 'DOC: ', var.__doc__
members = dir(var)
print 'Methods for ', var
for item in members:
if callable(getattr(var,item)):
print '\t\t',item
if isinstance(var,object):
print var, ' is instance of type object'
if hasattr(var,'__class__'):
if issubclass(var.__class__, str):
print 'is subclass of str'
else:
print 'Not subclass of str'
print '                                    '
print '************************************'
if __name__ == '__main__':
interrogate(1)
interrogate((1,))
interrogate([1])
interrogate('hello')
 　　运行结果：

ID:  41638144
Type:  <type 'int'>
Value:  1
CLASS:  <type 'int'>
DOC:  int(x[, base]) -> integer
Convert a string or number to an integer, if possible.  A floating point
argument will be truncated towards zero (this does not include a string
representation of a floating point number!)  When converting a string, use
the optional base.  It is an error to supply a base when converting a
non-string. If the argument is outside the integer range a long object
will be returned instead.
Methods for  1
__abs__
__add__
__and__
__class__
__cmp__
__coerce__
__delattr__
__div__
__divmod__
__float__
__floordiv__
__getattribute__
__getnewargs__
__hash__
__hex__
__index__
__init__
__int__
__invert__
__long__
__lshift__
__mod__
__mul__
__neg__
__new__
__nonzero__
__oct__
__or__
__pos__
__pow__
__radd__
__rand__
__rdiv__
__rdivmod__
__reduce__
__reduce_ex__
__repr__
__rfloordiv__
__rlshift__
__rmod__
__rmul__
__ror__
__rpow__
__rrshift__
__rshift__
__rsub__
__rtruediv__
__rxor__
__setattr__
__str__
__sub__
__truediv__
__xor__
1  is instance of type object
Not subclass of str
************************************
ID:  43539600
Type:  <type 'tuple'>
Value:  (1,)
CLASS:  <type 'tuple'>
DOC:  tuple() -> an empty tuple
tuple(sequence) -> tuple initialized from sequence's items
If the argument is a tuple, the return value is the same object.
Methods for  (1,)
__add__
__class__
__contains__
__delattr__
__eq__
__ge__
__getattribute__
__getitem__
__getnewargs__
__getslice__
__gt__
__hash__
__init__
__iter__
__le__
__len__
__lt__
__mul__
__ne__
__new__
__reduce__
__reduce_ex__
__repr__
__rmul__
__setattr__
__str__
(1,)  is instance of type object
Not subclass of str
************************************
ID:  43387600
Type:  <type 'list'>
Value:  [1]
CLASS:  <type 'list'>
DOC:  list() -> new list
list(sequence) -> new list initialized from sequence's items
Methods for  [1]
__add__
__class__
__contains__
__delattr__
__delitem__
__delslice__
__eq__
__ge__
__getattribute__
__getitem__
__getslice__
__gt__
__hash__
__iadd__
__imul__
__init__
__iter__
__le__
__len__
__lt__
__mul__
__ne__
__new__
__reduce__
__reduce_ex__
__repr__
__reversed__
__rmul__
__setattr__
__setitem__
__setslice__
__str__
append
count
extend
index
insert
pop
remove
reverse
sort
[1]  is instance of type object
Not subclass of str
************************************
ID:  43539936
Type:  <type 'str'>
Value:  'hello'
CLASS:  <type 'str'>
DOC:  str(object) -> string
Return a nice string representation of the object.
If the argument is a string, the return value is the same object.
Methods for  hello
__add__
__class__
__contains__
__delattr__
__eq__
__ge__
__getattribute__
__getitem__
__getnewargs__
__getslice__
__gt__
__hash__
__init__
__le__
__len__
__lt__
__mod__
__mul__
__ne__
__new__
__reduce__
__reduce_ex__
__repr__
__rmod__
__rmul__
__setattr__
__str__
capitalize
center
count
decode
encode
endswith
expandtabs
find
index
isalnum
isalpha
isdigit
islower
isspace
istitle
isupper
join
ljust
lower
lstrip
partition
replace
rfind
rindex
rjust
rpartition
rsplit
rstrip
split
splitlines
startswith
strip
swapcase
title
translate
upper
zfill
hello  is instance of type object
is subclass of str
************************************