list.js

const compose = (g) => (f) => (x) => g(f(x))
const flip = (f) => (a) => (b) => f(b)(a)
const rec = (f) => (...args) => f((...args) => rec(f)(...args), ...args)

const listCons = (x) => (y) => (m) => m(x)(y)
const listHead = (z) => z((p) => (_) => p)
const listTail = (z) => z((_) => (q) => q)
const listCase = (f) => (n) => (z) => (z === null ? n : f(listHead(z))(listTail(z)))

const map = (f) => listCase((h) => (t) => listCons(f(h))(map(f)(t)))(null)
const reduce = (f) => (n) => listCase((h) => (t) => reduce(f)(f(n)(h))(t))(n)
const filter = (f) => listCase((h) => (t) => ((r) => (f(h) ? listCons(h)(r) : r))(filter(f)(t)))(null)

const length = reduce((a) => (_) => a + 1)(0)
const empty = listCase((_) => (_) => false)(true)
const reverse = reduce(flip(listCons))(null)
const intersperse = (sep) => listCase((x) => (xs) => listCons(x)(rec((prependToAll, sep) => listCase((x) => (xs) => listCons(sep)(listCons(x)(prependToAll(sep)(xs))))(null))(sep)(xs)))(null)

const toString = compose((str) => (str === '' ? 'null' : `(list ${str})`))(compose(reduce((res) => (acc) => `${res}${acc}`)(''))(compose(intersperse(' '))(map((x) => `${x}`))))
const fromArray = (arr) => arr.reverse().reduce((res, elm) => listCons(elm)(res), null)

const data = fromArray(new Array(10).fill().map((_, n) => n))
length(data)
toString(map((n) => `[${n}]`)(data))
toString(filter((n) => n % 2 === 0)(data))
length(filter((n) => n % 2 !== 0)(data))
empty(data)
toString(reverse(data))
toString(fromArray([]))