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JavaScript

Joe Anderson
Joe Anderson
1,442 Points
Posted by Joe Anderson
Joe Anderson
1,442 Points

How does the setState function know we are adding the score to a specific player when it's just updating "score"?

I'm trying to figure out the logic behind our handler in the App.js file:

handleScoreChange = (index, delta) => {
  this.setState( prevState => ({
    score: prevState.players[index].score += delta,
  }));
}

How does the app know which user is being updated when the setState is targeting "score"? I would normally think we would have to use: 

handleScoreChange = (index, delta) => {
  this.setState( prevState => ({
    players[index].score: prevState.players[index].score += delta,
  }));
}

But we don't don't need to do this and I'm wondering why and how?