ok, so, I was doing this before and its working:

let array = [];
if (blablabla) array = ["foo","bar"];
else array = ["this", "that"];
FunctionImUsing(array)

And then the method will receive the array correctly and no problem.

this.FunctionImUsing = function (array) {
//works with the array inside the function. No problem
}

However, I wanted to do this:

if (blablabla) FunctionImUsing(["foo","bar"]);
else FunctionImUsing(["this","that"]);

But it doesnt work. the method receives only the first element and not the full array. How can I force the receiving variable to be an array?

I tried this

this.FunctionImUsing = function (array[]) {

but Javascript wont let me do that (Unexpected Token). I wanted to force the receiving variable of a function to be an array.