How to pass all element of a list as parameter of a function without passing the list as argument-CodePudding

This is the example :

def testB(argA, argB):
    #USER CODE

def testA(argA, argB, argC):
    #USER CODE


def funcExecuter(func, nbArgs, *argv):
    #TODO


funcExecuter(testA, 3, 1, 2, 3)
funcExecuter(testB, 2, 1, 2)

I want to implement a function (here funcExecuter) that execute the function func with its arguments that are in argv. Thoses functions got undefined number of parameters. But i can't call

func(*argv)

cause the actual function testA, needs three parameters not one. So i need to uses argv list to call the function func with all its parameters.

Is this possible ? Best regards.

CodePudding user response：

It looks like what you do is the correct method.

Example:

def testB(argA, argB):
    print(f'{argA=}')
    print(f'{argB=}')

def testA(argA, argB, argC):
    print(f'{argA=}')
    print(f'{argB=}')
    print(f'{argC=}')

def funcExecuter(func, nbArgs, *argv):
    return func(*argv)

print('test1')
funcExecuter(testA, 3, 'a', 'b', 'c')
print('test2')
funcExecuter(testB, 2, 'a', 'b')

output:

test1
argA='a'
argB='b'
argC='c'
test2
argA='a'
argB='b'

ensuring the correct number of parameters

If you want to truncate or pad the parameters:

def testA(argA, argB, argC):
    print(f'{argA=}')
    print(f'{argB=}')
    print(f'{argC=}')

def funcExecuter(func, nbArgs, *argv):
    return func(*(list(argv[:nbArgs]) [None]*(nbArgs-len(argv))))

print('test1')
funcExecuter(testA, 3, 'a', 'b', 'c')
print('test2')
funcExecuter(testA, 3, 'a', 'b', 'c', 'd')
print('test3')
funcExecuter(testA, 3, 'a', 'b')

output:

test1
argA='a'
argB='b'
argC='c'
test2
argA='a'
argB='b'
argC='c'
test3
argA='a'
argB='b'
argC=None

NB. this is a simple example here, of course you can have a more complex check

CodePudding user response：

Why don't you use func(*argv) and just throw an exception if they pass less than 3 arguments?