Can you explain how the "reduce" function can be implemented using an interface in TypeScript?

Can you explain the "reduce" function using an interface in TypeScript? https://i.stack.imgur.com/X1VxL.png

Answer №1

// condition for when no initial value is provided
reduce(callbackfn: (prevVal: T, currVal: T, index: number, arr: T[]) => T): T;
// condition for when initial value is provided
reduce(callbackfn: (prevVal: T, currVal: T, index: number, arr: T[]) => T, initialValue: T): T;

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