CrossEye

var first = (function() {
    var chainNames = ["then", "andThen", "next"];
    var endChainNames = ["finally", "andFinally", "last"];
    var chain = function(fn) {
        var f1 = function(g) {
            var func = function() {return g.call(this, fn.apply(this, arguments));};
            chain(func);
            return func;
        };
        var f2 = function(g) {

CrossEye

// Based on a discussion with Michael Haufe:
//   https://groups.google.com/group/jsmentors/browse_thread/thread/d028fb0041f93a27
// Not really recommended for anything but the fun of knowing it can be done!

var omega = function() {
    var queue = [];
    var valueOf = Function.prototype.valueOf;
    Function.prototype.valueOf = function() {
        queue.push(this);
        return 1;  // not needed now, but could be used later to distinguish operators.

CrossEye

// clean and pure:
function cons(x, y) {
    return function(pick) {
        return pick(x, y);
    }
}
 
// does more stuff:
function cons(x, y) {
    var fn = function(pick) {

CrossEye

inspired to understand this from:

• http://raganwald.com/2013/03/28/trampolines-in-javascript.html
• http://bilby.brianmckenna.org/#trampoline see http://en.wikipedia.org/wiki/Trampoline_(computing)

compare with https://github.com/Gozala/js-tail-call/blob/master/core.js for speed (after refactoring to work like his does)

http://jsperf.com/tail-call-head-to-head

CrossEye

var fibonacci = (function() {
    var fib = function(curr, next, n) {
        return  (n === 0) ? curr : fib(next, curr + next, n - 1);
    };
    return function(n) {
        return fib(0, 1, n);
    }
}());

CrossEye

Function.prototype.compose = function(g) {
    var fn = this;
    return function() {
        return fn.call(this, g.apply(this, arguments));
    };
};

Function.prototype.pipe = function(g) {
    var fn = this;
    return function() {

CrossEye

var compose = function compose(f) {
    var queue = f ? [f] : [];
    var fn = function fn(g) {
        if (arguments.length) {
            queue.push(g);
            return fn;
        }
        return function() {
            var args = Array.prototype.slice.call(arguments);
            queue.forEach(function(func) {

CrossEye

(function(global) {
    var types = function(obj) {
        throw new TypeError("fmap called on unregistered type: " + obj);
    };

    // inefficient as hell, but as long as there aren't too many types....
    global.Functor = function(type, defs) {
        var oldTypes = types;
        types = function(obj) {
            if (type.prototype.isPrototypeOf(obj)) {

CrossEye

Interesting and yet frightening technique

Run the following code against [Ramda][ramda].

// Simple predicate to test whether a number is even
var even = function(n) {return (n % 2) === 0;};

// Generates an infinite list of Fibonacci numbers

var fibsgen = generator(

CrossEye

(function(global) {
    // TODO: Make a tree structure from type objects' optional `parentKey` properties.  Do a depth-first search of
    // this tree instead of the simple linear search of `Object.keys`.
    var types = {};

    global.Functor = function(config) {
        types[config.key] = config;
    };

    global.fmap = curry(function(f, obj) {