/** @module maybe-functions.ts */
import { WidenType } from './helper-types';
import { Maybe } from './maybe';
export declare const safeInit: <A>(as: A[]) => Maybe<A[]>;
export declare const safeHead: <A>(as: A[]) => Maybe<A>;
export declare const safeLast: <A>(as: A[]) => Maybe<WidenType<A>>;
export declare const safeTail: <A>(xs: A[]) => Maybe<A[]>;
declare type PossibleKeyValue<A, O> = A extends keyof O ? keyof O[A] : {};
/**
 * takes an key (or index) and an array or object and returns
 * a Maybe. A Just containing the value of that object at key
 * or a Nothing if there is no value at the key index.
 */
export declare function safeProp<O, A>(k: A, obj: O): Maybe<PossibleKeyValue<A, O>>;
export declare function safeProp<O, A>(k: A): (obj: O) => Maybe<PossibleKeyValue<A, O>>;
export declare function safeIndexValue<A extends any[], I extends number>(index: I, arr: A & Array<{}>): Maybe<A[I]>;
export declare function safeIndexValue<I extends number>(index: I): <A extends any[]>(arr: A) => Maybe<A[I]>;
declare type StripAllNullValue<A extends object> = {
    [I in keyof A]: A[I] extends infer U ? U extends undefined | null ? never : U : never;
};
export declare const maybeAllValues: <O extends object | [any, ...any[]]>(o: O) => Maybe<StripAllNullValue<O>>;
export {};