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// https://tc39.es/ecma262/multipage/indexed-collections.html#sec-array.prototype.at

// Technically the specs also allow non-numeric types to be passed as index.

// However, TypeScript types the `Array.at` index param as number so we also expect only numbers

// This behaviour also matches the implementation of other Array functions in lualib.

export function __TS__ArrayAt<T>(this: T[], relativeIndex: number): T | undefined {

const absoluteIndex = relativeIndex < 0 ? this.length + relativeIndex : relativeIndex;

if (absoluteIndex >= 0 && absoluteIndex < this.length) {

return this[absoluteIndex];

}

return undefined;

}