import type { Bindings } from "../types.js";
/**
 * Access environment variables in your Edge-first application.
 */
export declare class Env {
    protected bindings: Bindings;
    constructor(bindings: Bindings);
    /**
     * Retrieve a value from the environment variables.
     * If the key is not found, an error is thrown.
     * An optional fallback value can be provided.
     * @param key The key to fetch from the environment variables.
     * @param fallback An optional fallback value to return if the key is not found.
     * @returns
     */
    fetch<Key extends keyof Bindings>(key: Key, fallback?: Bindings[Key]): Bindings[Key];
}