Provides a syntax for prototypal inheritance that also allows for arrays that inherit from a custom prototype
Proto Create
This module produces a function that creates and returns a target object which inherits from another object. The syntax used internally is "Object.create()" and this module is meant to provide a cleaner and better looking solution with the added benefit of "sub-classing" arrays, or effectively having an array inherit from any object (including null). The benefit of this is that you do not have to pollute Array.prototype when a custom array method is desired.
Thank you to kangax for the article on subclassing arrays. I used his method of creating an object and giving it the special characteristics of an array manually. The article can be seen here: http://perfectionkills.com/how-ecmascript-5-still-does-not-allow-to-subclass-an-array/
The argument of the function must be an object. The accepted optional properties are:
[ proto ] : the desired prototype of the newly created target object. if [ target ] is an array, [ proto ] defaults to Array.prototype, otherwise it defaults to Object.prototype
[ target ] : The new object to be created. This may be an array. Literal syntax is recommended since a shallow copy of the properties will take place.
[ descriptors ] : The descriptors of the object may be defined here.
If both [ target ] and [ descriptors ] are not defined, the function will return an empty object.
Install
npm install proto-create
Usage
const create = require("proto-create");
// creating an object that inherits from Object.prototype to be used as a new prototype
let myObjectPrototype = create({
proto: Object.prototype,
target: { a: 1 }
});
// creating an object that inherits from "myObjectPrototype"
let x = create({
proto: myObjectPrototype,
target: { b: 2 }
});
console.log(x.b, x.a, x.toString); // 2, 1, [Function: toString]
// creating an object to be used as a prototype for an array, which inherits from Array.prototype
let myArrayPrototype = create({
proto: Array.prototype,
descriptors: {
last: {
value: function () {
return this[this.length - 1];
}
}
}
});
// creating an array which inherits from "myArrayPrototype", which in turn inherits from Array.prototype
let y = create({
proto: myArrayPrototype,
target: [32, 43, 54, 65]
});
console.log(y.last(), y.map(x => 2 * x)); // 65, [ 64, 86, 108, 130 ]
HomePage
https://github.com/continuousElectronics/proto-create#readme
Repository
git+https://github.com/continuousElectronics/proto-create.git