javascript - what does fn.apply(fn, []) do? -

i have piece of code accepts fn argument , stores in object property.

var obj = {};  function anotherfn(fn){    obj["name"] = fn.apply(fn, []); }  function google(){     console.log("hello"); } anotherfn(google); console.log(obj.name); 

what not understanding fn.apply(fn,[]) code , purpose. use call , apply method when want execute fn in different this/context.

but fn.apply(fn, []) here?. confusion why can't do

obj["name"] = fn(); 

fn.apply(fn, []) calls function stored in fn context (the value of this while executing function) of fn, , arguments contained within [] (no arguments).

it seems odd call apply in way, when have been equivalent call fn.call(fn).

fn() not appropriate replacement, fn() execute in global context, means value of this within function window (assuming browser environment).