javascript - Ramda如何将参数传递给高阶函数？

Question

我正在学习函数式编程 here ，并遇到下面的代码

const wasBornInCountry = person => person.birthCountry === OUR_COUNTRY
const wasNaturalized = person => Boolean(person.naturalizationDate)
const isOver18 = person => person.age >= 18

const isCitizen = person => wasBornInCountry(person) || wasNaturalized(person)

const isEligibleToVote = person => isOver18(person) && isCitizen(person)

可以缩短为以下

const isCitizen = either(wasBornInCountry, wasNaturalized)
const isEligibleToVote = both(isOver18, isCitizen)

我似乎无法理解

const isCitizen = person => wasBornInCountry(person) || wasNaturalized(person)

可以翻译成如下:

const isCitizen = either(wasBornInCountry, wasNaturalized)

我们如何将参数person传递给wasBornInCountry和wasNaturalized？如果我希望使用两个参数调用 isCitizen 该怎么办？我们如何知道哪个参数将传递给 wasBornInCountry 以及哪个参数将传递给 wasNaturalized？

Answer 1

How do we pass the parameter person into wasBornInCountry and wasNaturalized?

你不知道。由任一生成的函数都可以。

What if I wish to call isCitizen with two parameters?

然后确保您传递给任一的两个函数都接受两个参数。

const same = (x, y) => x == y;
const ten = (x, y) => x == 10 || y == 10;
const f = R.either(same, ten);
console.log([f(1, 1), f(2, 1), f(10, 3)])

How we know which parameter gonna be passed to wasBornInCountry and which parameter to wasNaturalized?

去看看你的原始代码:

const isCitizen = person => wasBornInCountry(person) || wasNaturalized(person)

• 将 person 参数传递给 wasBornInCountry
• 将 person 参数传递给 wasNaturalized

只有一个参数。它被传递给两个函数。

如果有多个参数，那么它们都会传递给两个函数。