Question

I want to create a javascript class of my own. My question is, how do i create a function with two differents effects depending on the context.

Here is an example :

function Matrix(str) {
this.G = 2 dim array;
this.e = function(x,y){
    G[x][y] = 3 // if the user types myGraph.e(1,1) = 3;
    return G[x][y] // if user call myGraph.e(1,1);
}

So how can I have two different results with only one function ? myGraph.e(1,1) = 3 and myGraph.e(1,1)

Thx !

Answer 1

Slightly modifying @Esalija’s answer:

this.e = function(x, y, value) {
    if (typeof value !== 'undefined') {
        this.G[x][y] = value;
    }
    return this.G[x][y];  // always return the value
}

NB: it’s more common for the first dimension of a 2-D array to represent y, not x.