-- note: JS version can return anything that's truthy, but that won't work for us since Lua deviates (0 is truthy)

type callbackFn<T> = (element: T, index: number, array: Array<T>) -> boolean
type callbackFnWithThisArg<T, U> = (thisArg: U, element: T, index: number, array: Array<T>) -> boolean
