Parent constructor call overridden functions before all child constructors are finished

Question

ECMAScript 6 (Harmony) introduces classes with ability to inherit one from another. Suppose I have a game and some basic class to describe basic things for bot

Answer 1

The following code will do what you want, though it is currently only supported in FF 41+ and Chrome 47+ (see https://kangax.github.io/compat-table/es6/)

class Bot{
    constructor(){
        if (new.target === Bot)
            this.render();
    }
    render(){
        console.log('Bot rendered');
    }
}

class DevilBot extends Bot{
    constructor(){
        super();
        this.color = 0xB4D333;
        this.render();
    }
    render(){
        console.log('DevilBot rendered with', this.color);
    }
}

var bot = new Bot();       // Bot rendered
var dev = new DevilBot();  // DevilBot rendered with 11850547