python - 如何制作一个像lisp的 'mapcar'一样工作的python函数

Question

我想知道如何制作一个与 lisp 的 mapcar 功能相同的 python 函数。

来自mapcar lisp documentation :

mapcar operates on successive elements of the lists. function is applied to the first element of each list, then to the second element of each list, and so on. The iteration terminates when the shortest list runs out, and excess elements in other lists are ignored. The value returned by mapcar is a list of the results of successive calls to function.

例如，

list1 = [1, 2, 3, 4, 5]
list2 = [5, 4, 3, 2, 1]

def sum(firstNumber, secondNumber):
    return firstNumber + secondNumber

sumOfLists = mapcar(sum, list1, list2)

print(sumOfLists)
# [6, 6, 6, 6, 6]

Answer 1

使用map，还有一个operator用于添加operator.add:

>>> import operator
>>> list(map(operator.add, list1, list2))
[6, 6, 6, 6, 6]

来自documentation . map 将函数作为第一个参数，以及可变数量的iterable 参数。关键是该函数应采用与提供给 map 的可迭代对象一样多的参数。这是唯一要考虑的“限制”。所以，例如:

map(lambda x: x+1,         range(10))
map(lambda x, y: x+y,      range(10), range(10))
map(lambda x, y, z: x+y+z, range(10), range(10), range(10))

等等……

它也可以接受用户定义的任何其他函数:

def checkString(s):
    return isinstance(s, str) and len(s) > 10

>>> list(map(checkString, ["foo", "fooooooooooooooooooooo"]))
[False, True]