Add new datatypes

File: index.js

var math = require('../../../index');

// import the new type MyType and the function `add` in math.js

// create a shortcut to the new type.
var MyType = math.type.MyType;

// use the new type
var ans1 = math.add(new MyType(2), new MyType(3));  // returns MyType(5)
console.log(ans1.toString());                       // outputs 'MyType:5'

// numbers will be converted to MyType
var ans2 = math.add(new MyType(4), 7);              // returns MyType(11)
console.log(ans2.toString());                       // outputs 'MyType:11'

File: MyType.js

// Note: This file is used by the file ./index.js

// factory function which defines a new data type MyType
function factory(type, config, load, typed) {

  // create a new data type
  function MyType (value) {
    this.value = value;
  MyType.prototype.isMyType = true;
  MyType.prototype.toString = function () {
    return 'MyType:' + this.value;

  // define a new data type
    name: 'MyType',
    test: function (x) {
      // test whether x is of type MyType
      return x && x.isMyType;

  // define conversions if applicable
    from: 'number',
    to: 'MyType',
    convert: function (x) {
      // convert a number to MyType
      return new MyType(x);

  // return the construction function, this will
  // be added to math.type.MyType when imported
  return MyType;
} = 'MyType';
exports.path = 'type';        // will be imported into math.type.MyType
exports.factory = factory;
exports.lazy = false;         // disable lazy loading as this factory has side
                              // effects: it adds a type and a conversion.

File: myAdd.js

// Note: This file is used by the file ./index.js

function factory (type, config, load, typed) {
  // create a new typed function using MyType
  // when imported in math.js, this will extend the
  // existing function `add` with support for MyType
  return typed('add', {
    'MyType, MyType': function (a, b) {
      return new type.MyType(a.value + b.value);
} = 'add';
exports.factory = factory;

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