2.0.0 • Published 8 years ago

ski v2.0.0

Weekly downloads
1,194
License
CC-0
Repository
github
Last release
8 years ago

ski

eponymous functions from the SKI calculus

installation

$ npm install ski

usage

var ski = require(ski)
var S = ski.S
var K = ski.K
var I = ski.I

var log = console.log.bind(console)

var tenner = S(K, log, 10)
// 10 logged to console
// tenner === 10

var truth = ski.K(true)
truth()
// => true

ski.I(5)
// => 5

The module is also split into files, so you can use commonjs path syntax to only load the function(s) you need:

var S = require('ski/s')
var K = require('ski/k')
var I = require('ski/i')

api

descriptions adapted from wikipedia:

I = function (x), the identify function

I returns its argument:

I(x) => x

K = function (x), the constant function

K, when applied to any argument x, yields a one-argument constant function Kx , which, when applied to any argument, returns x:

K(x) => (y) => x

S = function (x, y, z), the substitution function

S is a substitution operator. It takes three arguments and then returns the first argument applied to the third, which is then applied to the result of the second argument applied to the third. More clearly:

S(x, y, z) === x(z)(y(z))

license

CC 0 (public domain)