Using apply() vs call(), which one to use in this case? [duplicate]

Question

Taking a look at code from Leaflet api

My question is why wrapperFn.apply(context, args);</code> and <code>fn.apply(context, args); using apply() and not call().

How do you know which one to use ?

Confused because I don't know ahead of time if my passing function is using an array or not.

limitExecByInterval: function (fn, time, context) {
    var lock, execOnUnlock;

    return function wrapperFn() {
        var args = arguments;

        if (lock) {
            execOnUnlock = true;
            return;
        }

        lock = true;

        setTimeout(function () {
            lock = false;

            if (execOnUnlock) {
                wrapperFn.apply(context, args);
                execOnUnlock = false;
            }
        }, time);

        fn.apply(context, args);
    };
},

Answer 1

Apply takes a single array of arguments, useful for method chaining, the javascript equivalent of calling super. in Java etc.

function makeNoise() {
   Foo.prototype.makeNoise.apply(this, arguments);
}

Call takes list of parameters, more useful other situations where the arguments are only available as single variables.

fn.call(this, x, y, z);

which would just be shorthand for

fn.apply(this, [x, y, z])

Given you have an array of arguments you need to use apply()