How to dynamically add members to class
My question can be simply illustrated by this code:
def proceed(self, *args): myname = ??? func = getattr(otherobj, myname) result = func(*args) # result = ... process result .. return result class dispatch(object): def __init__(self, cond=1): for index in range(1, cond): setattr(self, 'step%u' % (index,), new.instancemethod(proceed, self, dispatch)
After that instance of dispatch must have step1..stepn members, t开发者_开发百科hat call corresponding methods in otherobj. How to do that? Or more specifically: What must be inserted in proceed after 'myname =' ?
Not sure if this works, but you could try to exploit closures:
def make_proceed(name):
def proceed(self, *args):
func = getattr(otherobj, name)
result = func(*args)
# result = ... process result ..
return result
return proceed
class dispatch(object):
def __init__(self, cond=1):
for index in range(1, cond):
name = 'step%u' % (index,)
setattr(self, name, new.instancemethod(make_proceed(name), self, dispatch))
If the methods are called step1 to stepn, you should do:
def proceed(myname):
def fct(self, *args):
func = getattr(otherobj, myname)
result = func(*args)
return result
return fct
class dispatch(object):
def __init__(self, cond=1):
for index in range(1, cond):
myname = "step%u" % (index,)
setattr(self, myname, new.instancemethod(proceed(myname), self, dispatch))
If you don't know the name, I don't understand what you're trying to achieve.
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