Object.prototype.boundTo

gistfile1.js

"use strict";

(function(){

    var cache = new WeakMap();
    
    Object.prototype.boundTo = function(fct){
        var obj = this;
        
        var objMap = cache.get(fct);
        
        if(objMap === undefined){
            objMap = new WeakMap();
            cache.set(fct, objMap);
        }
        
        var bound = objMap.get(obj);
        
        if(bound === undefined){
            bound = fct.bind(obj);
            objMap.set(obj, bound);
        }
    
        return bound;
    };

})();