import { type DecodeContext, type RTError, Type } from './type.js';
import { type Result } from './utils.js';
type ElementType<T extends ReadonlyArray<unknown>> = T extends ReadonlyArray<infer ElementType> ? ElementType : never;
export declare class UnionType<T extends ReadonlyArray<unknown>> extends Type<ElementType<T>> {
    members: {
        [K in keyof T]: Type<T[K]>;
    };
    constructor(members: {
        [K in keyof T]: Type<T[K]>;
    });
    print(): string;
    decode(u: unknown, opts: DecodeContext): Result<ElementType<T>, RTError>;
    validate(v: ElementType<T>, opts: DecodeContext): Promise<Result<ElementType<T>, RTError>>;
    validateSync(v: ElementType<T>, opts: DecodeContext): Result<ElementType<T>, RTError>;
    deepMap(fn: (t: Type<unknown>) => Type<unknown>): Type<unknown>;
}
export declare function union<T extends ReadonlyArray<unknown>>(...members: {
    [K in keyof T]: Type<T[K]>;
}): Type<ElementType<T>>;
export {};