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Marcell Ciszek
Marcell Ciszek
7,255 Points

square brackets, why?

    playToken() {
        let spacec = this.board.spaces;
        let activeToken = this.spaces[activePlayer.activeToken];
        let targetSpace = null

        for (let token of this.column ){
            if ( token !== column) {
                game = false

2 Answers

Chris Shaw
Chris Shaw
26,676 Points

Hi Marcell Ciszek,

Square brackets denote a key selection within an object. In the example you have given above, you are using the activeToken property on the activePlayer object to find a position within the this.spaces array.

The same syntax can too be used for objects and strings alike since they all inherit the same behaviour. E.g.

const foo = 'bar'[1] // yields "a"
const bar = { foo: 'Hello', bar: 'World' }['foo'] // yields "Hello"

Hope that helps!

Zack Jackson
Zack Jackson
30,220 Points

It's selecting the index of the spaces array using activePlayer.activeToken as the index. It's hard to see in your code when the activePlayer.activeToken is not returning a value for you to see. Try console logging it.

Here's a simplified example of what your code is setup to do:

spaces = [ "a", "b", "c" ];
return spaces[0];



return spaces[2];