The original answer below was written in 2008. Since then, Python 3.10 (2021) introduced the match
-case
statement which provides a first-class implementation of a "switch" for Python. For example:
def f(x):
match x:
case 'a':
return 1
case 'b':
return 2
case _:
return 0 # 0 is the default case if x is not found
The match
-case
statement is considerably more powerful than this simple example.
You could use a dictionary:
def f(x):
return {
'a': 1,
'b': 2,
}[x]
Variables declared inside the class definition, but not inside a method are class or static variables:
>>> class MyClass:
... i = 3
...
>>> MyClass.i
3
As @millerdev points out, this creates a class-level i
variable, but this is distinct from any instance-level i
variable, so you could have
>>> m = MyClass()
>>> m.i = 4
>>> MyClass.i, m.i
>>> (3, 4)
This is different from C++ and Java, but not so different from C#, where a static member can't be accessed using a reference to an instance.
See what the Python tutorial has to say on the subject of classes and class objects.
@Steve Johnson has already answered regarding static methods, also documented under "Built-in Functions" in the Python Library Reference.
class C:
@staticmethod
def f(arg1, arg2, ...): ...
@beidy recommends classmethods over staticmethod, as the method then receives the class type as the first argument, but I'm still a little fuzzy on the advantages of this approach over staticmethod. If you are too, then it probably doesn't matter.
Best Answer
You absolutely can use
is
in aswitch
block. See "Type Casting for Any and AnyObject" in the Swift Programming Language (though it's not limited toAny
of course). They have an extensive example: