node.js - node export module unknown console log "undefined" -

so i'm learning export modules node.js

in test.js have (test.js module writen)

var library={     name:"timmy",     greet:function(name){         console.log("hello "+ name);     } } module.exports.library=library; 

in server.js have:

var test=require('./test.js');  console.log(test.library.greet()) 

then when run node server.js in terminal, gives this:

hello timmy library. undefined 

what "undefined" mean? error?

i found similar question here, complicated example couldn't understand.. node module export returning undefined

so here whats happening: console inside server.js file prints return of function call. since function call (test.library.greet()) doesn't return explicitly return undefined implicitly.

thats whats getting printed.