Javascript: check if function exists, rename if so and create function from string

Question

I am trying to get JS to check for a function if it exists, if it does then it renames the string then creates the function based on that string. I got the first part I just can figure out how to create the function name based on a string:

var myMicro = 'getMicro';

if (typeof window[myMicro] === "function") {
    myMicro = 'getMicro2';
} else {
    myMicro = 'getMicro';
}

function window[myMicro] (obj, place, func, params, finishFUNC) {

}

The first part works, but creating the function with this string doesn't seem to work afterwords.

Answer 1

You can probably do this:

window[myMicro] = function (obj, place, func, params, finishFUNC) {

}

Answer 2

It is good not to overwrite global variables as well:

var myMicro = "getMicro" in window ? "getMicro2" : "getMicro";
window[myMicro] = function(obj, place, func, params, finishFUNC) {
    // ...
};