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Start your free trialTrevor Maltbie
Full Stack JavaScript Techdegree Graduate 17,021 PointsHow does this.tokens access the class Tokens for the dropped property?
get unusedTokens() {
return this.tokens.filter(token => !token.dropped);
}
I see that in the class Player we have this.tokens = this.createTokens(21)
but how does the filter method get access to this.dropped
in the class Tokens?
1 Answer
Steven Parker
231,198 PointsThe term "this" is only used inside the current class instance. Outside, the instance name is combined with the attribute name using the membership operator (the period).
So as the filter is checking the "this.tokens" array one at a time, each one is assigned the name "token" and "token.dropped" accesses its "dropped" property.
Daryl Monte
Python Development Techdegree Graduate 25,409 PointsDaryl Monte
Python Development Techdegree Graduate 25,409 PointsHi Steven, I am still a bit confuse with the code above.
Where did we get the token in (token => !token.dropped) ? Is this related to the Token class in Token.js or is this a new variable?
Same in the activePlayer getter: return this.players.find(player => player.active) Where did the player in the parenthesis come from? Is this related to the Player class in Player.js or is this a new variable?
Thank you.
Steven Parker
231,198 PointsSteven Parker
231,198 PointsIn this case,
token
is the parameter of the arrow function being defined here (so yes, sort of a new variable).And yes, the filter applies this function to each item in the tokens array.