我希望能够动态地向python类添加函数,而不是事先知道它们的名字

sta*_*art 1 python methods class dynamic instance

假设我有一个名单.我希望能够动态地将这些实例函数添加到类实例中.我知道类型.MethodType但我从这里到这里有点新手.基本上我想做的是:

class foo( object ):
     def __init__(self):
         pass

f = foo()
names = ["a","b","c"]
for name in names:
    add name() to f  # not sure what to do here
    # what I wanted added to instance "f" is this for each name:
    def name(self, *args, **kwargs):
        print( "My name is %s" % inspect.stack()[0][3]   )       
        print( "__called, args=%r, **kwargs=%r" % (args, kwargs) )

f.a() # ==> calls f.a()
f.b(1,2,3) # calls f.b(1,2,3 )and so on
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Mar*_*ers 5

如果您将函数创建为嵌套函数,则更容易; name然后是从嵌套范围中获取的变量:

import types
def buildMethod(name, instance):
    def namefunc(self, *args, **kwargs):
        print "My name is %s" % name
        print "__called, args=%r, **kwargs=%r" % (args, kwargs)
    namefunc.__name__ = name
    setattr(instance, name, types.MethodType(namefunc, instance, type(instance)))

f = foo()
names = ["a","b","c"]
for name in names:
    buildMethod(name, f)
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这导致:

>>> f.a
<bound method instance.a of <__main__.foo instance at 0x100d8e560>>
>>> f.a.__name__
'a'
>>> f.a()
My name is a
__called, args=(), **kwargs={}
>>> f.b()
My name is b
__called, args=(), **kwargs={}
>>> f.c()
My name is c
__called, args=(), **kwargs={}
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