Question

In node.js, a tcp server has the following methods to listen:

server.listen(port, [host], [backlog], [listeningListener])
server.listen(path, [listeningListener])
server.listen(handle, [listeningListener])

I would like to create an application specific server which calls this lower level tcp server. I would like to provide my users with a listen method which just calls the right listen method of a tcp server.

Is there a way for me to avoid writing three different listen methods, and passing their arguments to the three tcp server’s listen methods? Will it pass on optional parameters?

Can I just do something like this (with slightly made up syntax):

myapp.listen(args*){
    tcpserver.listen(args*);
}

Answer 1

In JavaScript, all of a function’s arguments are always available under the name arguments, whether or not they also have their own names; so you can write:

myapp.listen(){
    tcpserver.listen.apply(tcpserver, arguments);
}

using the function Function.apply to forward arguments to the desired method-call.

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Edited to add: I should also clarify that although this:

In node.js, a tcp server has the following methods to listen […] the three tcp server’s listen methods […]

is consistent with the way the Node.js documentation describes things, it’s not strictly accurate. JavaScript doesn’t have any concept of function/method overloading; rather, it must be that a Server object has a single listen method that examines its first argument to determine which “overload” to execute.