export declare type Maybe<T> = Option<T> | undefined;
export declare type Option<T> = T | null;
export declare type Table<T> = {
    [key: string]: T;
};
export interface Class<T> {
    new (...args: any[]): T;
}
export declare namespace Class {
    function cast<T>(constructor: Class<T>, variable: string, value: any): T;
    function tryCast<T>(constructor: Class<T>, value: any): Option<T>;
}
export declare function assert(condition: boolean, message?: string, ...variables: any): void;
export declare function bail(message: string, ...variables: any[]): never;
export declare function expect<T>(value: Maybe<T>, message?: string, ...variables: any): T;
export declare function findMap<T, U>(items: Iterable<T>, fn: (item: T) => Maybe<U>): Maybe<U>;
export declare function filterMapValues<T, U>(items: Table<T>, fn: (item: T) => Maybe<U>): Table<U>;
export declare function warn(message: string, ...variables: any): void;
export declare function unreachable(): never;