/**
 * Pick one item uniformly at random from `items` using `rng` (a `() => number` in `[0, 1)`); returns undefined when empty.
 *
 * @capability weighted-pick pick one item from a set with an injected random source
 */
export declare function pickUniform<T>(rng: () => number, items: readonly T[]): T | undefined;
/** Pick one item with probability proportional to `weightOf(item)`; skips non-positive weights, returns undefined when nothing is eligible. */
export declare function pickWeighted<T>(rng: () => number, items: readonly T[], weightOf: (item: T) => number): T | undefined;