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import { Take_, λ } from "./types.ts";
/** * Turns `fun` into a unary function (a function that only accepts one * argument). * * Note: `fun` must accept at least one argument and must not require more than * one argument. * * @example * ``` * ['1', '2', '3'].map(unary(parseInt))  // -> [1, 2, 3] * ``` */const unary = <T extends λ<[any]>>(  fun: Parameters<T> extends [] ? never : T,): Unary<T> => ((arg: unknown) => (fun as any)(arg)) as any;
export default unary;
type Unary<T extends λ<[any]>> = λ<Take_<Parameters<T>, 1>, ReturnType<T>>;