import { Kind } from '../../kinds/index.js';
import { Functor } from '../functor';
import { TypeSkell } from '../../typeskell/index.js';
export declare namespace CoMonad {
    type $extract<F extends Kind> = TypeSkell<'F a ..e -> a', {
        F: F;
    }>;
    type $extend<F extends Kind> = TypeSkell<'(F a ..e -> b) -> F a ..e -> F b ..e', {
        F: F;
    }>;
    type $duplicate<F extends Kind> = TypeSkell<'F a ..e -> F (F a ..e) ..e', {
        F: F;
    }>;
}
/**
 * CoMonad is a typeclass that defines two operations, extract and extend.
 * It is a generalization of Functor.
 *
 * Laws:
 * - Left Identity: extract . extend f = f
 * - Right Identity: extend extract = id
 * - Associativity: extend f . extend g = extend (f . extend g)
 *
 */
export interface CoMonad<F extends Kind> extends Functor<F> {
    extract: CoMonad.$extract<F>;
    extend: CoMonad.$extend<F>;
}
export declare const duplicate: <F extends Kind>(coMonad: CoMonad<F>) => CoMonad.$duplicate<F>;