promises fun

parallel.js

var Q = require('q');

function printNumber(n) {
    return Q.fcall(function () {
        console.log("Number: ", n);
        return n;
    });
}

function printNumbers(numbers) {
    if (numbers.length === 0) {
        return;
    } else {
        var current = numbers.pop();
        console.log(current, numbers);
        return printNumber(current).then(function () {
            printNumbers(numbers);
        });
    }
}

Q.all(printNumber(1), printNumber(2), printNumber(3)).then(function () {
    console.log(arguments);
});

recursion.js

var Q = require('q');

function printNumber(n) {
    return Q.fcall(function () {
        console.log("Number: ", n);
        if (n % 3 === 0) {
            return Q.reject(n);
        } else {
            return n;
        }
    });
}

function printNumbers(numbers, errors) {
    if (numbers.length === 0) {
        return errors;
    } else {
        var current = numbers.pop();
        return printNumber(current).then(function () {
            return printNumbers(numbers, errors);
        }, function (rejection) {
            errors.push(rejection);
            return printNumbers(numbers, errors);
        });
    }
}

Q.fcall(function () {
    return printNumbers([1, 2, 3, 4, 5, 6], []);
}).then(function () {
    console.log(arguments);
});

sequential.js

var Q = require('q');

function getIndex() {
    var context = {};
    context.url = 'http://www.agilogy.com';
    return context;
}

function getSomething(context) {
    console.log("URL IS", context.url);
    context.something = "Something";
    return context;
}

Q.fcall(getIndex)
    .then(getSomething)
    .then(console.log);

sequential2.js

var Q = require('q');

function emptyContext(c) {
    return Q.fcall(function () {
        return c || {};
    });
}

function login(username) {
    return {
        token: 'username'
    };
}

function getIndex(uri, param) {
    return function (context) {
        context[param] = context[param] || {};
        context[param].index = {
            href: uri + '/index'
        };
        return context;
    };
}

function getStores(context) {
    return emptyContext(context)
        .then(getIndex('http://stores.com', 'stores'))
        .then(function (c) {
            c.stores.data = {};
            c.stores.data.stores = c.stores.index.href;
            return c;
        });
}

function getUserData(context) {
    return emptyContext(context)
        .then(getIndex('http://userdata.com', 'userdata'))
        .then(function (c) {
            c.userdata.data = {};
            c.userdata.data.stores = c.userdata.index.href;
            return c;
        });
}

function combine(context) {
    return Q.all(arguments).then(function (results) {
        /*for (var i in results) {
            context[i] = results[i];
        }*/
        context.a = 1;
        //console.log("context", context);
        return context;
    });
}

Q.fcall(login.bind(null, 'lolo'))
    .then(combine(getStores(), getUserData()))
    .then(console.log);