Iyer, Prasad C wrote:
> Thanks a lot for the reply.
> But I want to do something like this
>
> class BaseClass:
> def __init__(self):
> # Some code over here
> def __init__(self, a, b):
> # Some code over here
> def __init__(self, a, b, c):
> # some code here
>
> baseclass1=BaseClass()
> baseclass2=BaseClass(2,3)
> baseclass3=BaseClass(4,5,3)
In my experience, the vast majority of cases where you "want" function
overloading, you really just want sensible default parameters. Since
Python is dynamically typed, the other common use case in static-typed
language (to provide f(int,int), f(float,float), f(double,complex),
f(Momma,Poppa) equivalents) is entirely unnecessary.
Try:
class BaseClass:
def __init__(self, a = None, b = None, c = None):
if a == None:
<etc>
or (if you want to take any number of parameters)
class BaseClass:
def __init__(self, *args):
if len(args) == 0:
<etc>
Of course, this is assuming that the behaviour is radically different
based on the number of arguments, which is generally Poor Design. You
probably _REALLY_ want:
class BaseClass:
def __init__(self, a=SensibleDefault1, b=SensibleDefault2,
c=SensibleDefault3):
<etc>
As a concrete example of this, consider:
class Point:
def __init__(self, x=0, y=0, z=0):
<etc>
Then you can call it with:
originPoint = Point()
pointInX = Point(xloc)
pointInXYPlane = Point(xloc,yloc)
pointIn3DSpace = Point(xloc,yloc,zloc)
<note, normally I loathe CaMeLcAsE, but it's readable in this context>
Or if the Defaults aren't quite so simple, and sensible defaults depend
on previous values, use:
class BaseClass:
def __init__(self, a=SensibleDefault1, b=None, c=None):
if b==None:
b = stuff_involving(a)
if c==None:
c = stuff_involving(a,b)
<etc>
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