index.js
function forward(event, source, target) {
    source.on(event, target.emit.bind(target, event));
}
function forward(event, source, target) {
    source.on(event, target.emit.bind(target, event));
}
Forward events of the specified type from source emitter to target.
@param {string} event
@param {EventEmitter} source
@param {EventEmitter} target