proteus/node_modules/proteus/bind.js

A declarative way of creating objects, properties, and classes in ES5 JavaScript

var putil = require("proteus/util"),
    slice = putil.slice
;

module.exports = {
    /**
     * Return a function that is bound to call another function on the current
     * object, or the supplied one.
     * 
     * @method aliasMethod
     * @param {String} name Name of the method to alias
     * @param {Object} [scope] Object in which the function resides,
     *      and the scope to call the method in.
     * @return {Function}
     */
    aliasMethod: function (name, scope) {
        var args = putil.slice(arguments, 2);
        // NOTE: We do not use 'bind' because the named method may not exist
        // at the time this is invoked.
        return function () {
            var self = scope || this,
                fn = typeof name === "function" ? name : self[name]
            ;

            if (!fn) {
                throw Error("Alias function '" + name + "' does not exist.");
            }

            return fn.apply(self, args.concat(putil.slice(arguments)));
        };
    },
    /**
     * Delegate a function call to another object.
     * 
     * @method delegateMethod
     * @param {Object} obj The object to delegate to
     * @param {String} name Name of the function to delegate to on 'obj'
     * @param {Mixed} rest Additional arguments to prepend to the function call
     * @return {Function}
     */
    delegateMethod: function (obj, name /*, rest */) {
        var args = slice(arguments, 2),
            fn = obj[name]
        ;

        return fn.bind.apply(fn, [obj].concat(args));
    }
};