import { STM } from "@effect/core/stm/STM/definition/base";
import { Collection } from "@tsplus/stdlib/collections/Collection/definition";
import { Maybe } from "@tsplus/stdlib/data/Maybe/definition";
/**
 * Returns a successful effect with the head of the list if the list is
 * non-empty or fails with the error `None` if the list is empty.
 * @tsplus getter effect/core/stm/STM head
 * @tsplus location "@effect/core/stm/STM/operations/head"
 */
export declare function head<R, E, A>(self: STM<R, E, Collection<A>>): STM<R, Maybe<E>, A>;
//# sourceMappingURL=head.d.ts.map