TypeError: testFunction() missing 1 required positional argument: 's'-CodePudding

I see similar questions asked but in the simple scenario I am trying to understand what I am missing

class test:
    def testFunction(self,s:str):
        return s

print (test.testFunction("test"))

I keep getting

TypeError: testFunction() missing 1 required positional argument: 's'

CodePudding user response：

The above answer already mentions some "official" ways. Still if you want to directly fix the "TypeError: testFunction() missing 1 required positional argument: 's'". You just need to add a argument which is self (test class) like below:

class test:
    def testFunction(self,s:str):
        return s

print(test.testFunction(test, "x")) # x
print(test.testFunction) # <function test.testFunction at 0x0000018C3ADBE160>

Note that the function itself is an Object, so if you call it directly it will give the address of that object

CodePudding user response：

You first need to instantiate an object of the class test.

class test:
    def testFunction(self,s):
        return s

test_obj = test()
print (test_obj.testFunction("test"))

Or, if you have no need to reuse the object, you can do the more concise

class test:
    def testFunction(self,s):
        return s

print (test().testFunction("test"))

But if the object isn't reused, you may have no need to define a class at all. The above is more or less the same as running:

def testFunction(s):
     return s
    
print (testFunction("test"))