es5-class-ployfill
v0.1.2
Published
Use Class-likely in es5
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es5-class-ployfill
Use Class-likely in es5
Inspired by http://ejohn.org/blog/simple-javascript-inheritance/
Install
Node.js 4 or higher
$ npm install es5-class-ployfill --save
Usage
var Class = require('es5-class-ployfill');
// Shape
var Shape = Class.extend({
constructor: function() {
this.x = 0;
this.y = 0;
},
move: function(x, y) {
this.x += x;
this.y += y;
console.info('Shape moved.');
},
echo: function() {
console.log('I am Shape.');
}
});
// Rectangle
var Rectangle = Shape.extend({
constructor: function(w, h) {
this.w = w;
this.h = h;
this._super();
},
move: function(x, y) {
this._super(x, y);
console.info('Rectangle moved.');
},
area: function() {
console.log('Area is', this.w * this.h);
},
echo: function() {
console.log('I am Rectangle.');
}
});
// Square
var Square = Rectangle.extend({
constructor: function(w) {
this._super(w, w);
},
echo: function() {
console.log('I am Square.');
}
});
var rect = new Rectangle(2, 4);
var square = new Square(4);
console.log('Is rect an instance of Rectangle?', rect instanceof Rectangle);// true
console.log('Is rect an instance of Shape?', rect instanceof Shape);// true
console.log('Is rect an instance of Square?', rect instanceof Square);// false
rect.echo(); // Outputs, 'I am Rectange.'
rect.move(1, 1); // Outputs, 'Shape moved. Rectangle moved.'
rect.area(); // Outputs, 'Area is 8'
console.log('Is square an instance of Square?', square instanceof Square);// true
console.log('Is square an instance of Rectangle?', square instanceof Rectangle);// true
console.log('Is square an instance of Shape?', square instanceof Shape);// true
square.echo(); // Outputs, 'I am Square.'
square.area(); // Outputs, 'Area is 16'
API
Class.extend(proto)
proto
Define Function prototype, especially proto.constructor
is Function constructor