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export function last<T>(arr: T[]): T | undefined {
return arr[arr.length - 1];
}
export function randomPick<T>(arr: T[]): T | undefined {
return arr[Math.floor(Math.random() * arr.length)];
}
/** Return an array with an edited element at the given index. */
export function edit<T>(arr: T[], index: number, newValue: T): T[] {
return arr.map((value, i) => (i === index ? newValue : value));
}
type IterateReturn<T> = [
T,
{
isFirst: boolean;
isLast: boolean;
array: T[];
index: number;
length: number;
},
];
/**
* Returns an an iterator that iterates over the given array.
* Each returned item contains helpful properties, such as
* `isFirst`, `isLast`, `array`, `index`, and `length`
*
* @param array The array to iterate over.
* @returns An iterator that iterates over the given array.
*/
export function* iterate<T>(array: T[]): Generator<IterateReturn<T>> {
for (let i = 0; i < array.length; i++) {
yield [
array[i]!,
{
isFirst: i === 0,
isLast: i === array.length - 1,
array,
index: i,
length: array.length,
},
];
}
}
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