export type RailroadNode = {
    kind: 'terminal';
    text: string;
} | {
    kind: 'nonterminal';
    text: string;
} | {
    kind: 'comment';
    text: string;
} | {
    kind: 'skip';
} | {
    kind: 'seq';
    items: RailroadNode[];
} | {
    kind: 'choice';
    items: RailroadNode[];
} | {
    kind: 'optional';
    item: RailroadNode;
} | {
    kind: 'oneOrMore';
    item: RailroadNode;
    rep?: RailroadNode;
} | {
    kind: 'zeroOrMore';
    item: RailroadNode;
    rep?: RailroadNode;
} | {
    kind: 'diagram';
    items: RailroadNode[];
};
export type GrammarModel = {
    start: string;
    rules: {
        [name: string]: RailroadNode;
    };
    legend?: {
        token: string;
        meaning: string;
    }[];
    ignored?: {
        token: string;
        meaning: string;
    }[];
    meta?: {
        engine: string;
        [k: string]: any;
    };
};
export declare class RailroadError extends Error {
    node?: unknown;
    constructor(message: string, node?: unknown);
}
export type Item = RailroadNode | string;
export declare function norm(item: Item): RailroadNode;
export declare function Terminal(text: string): RailroadNode;
export declare function NonTerminal(text: string): RailroadNode;
export declare function Comment(text: string): RailroadNode;
export declare function Skip(): RailroadNode;
export declare function Sequence(...items: Item[]): RailroadNode;
export declare function Choice(...items: Item[]): RailroadNode;
export declare function Optional(item: Item): RailroadNode;
export declare function OneOrMore(item: Item, rep?: Item): RailroadNode;
export declare function ZeroOrMore(item: Item, rep?: Item): RailroadNode;
export declare function Diagram(...items: Item[]): RailroadNode;
export declare function toText(node: Item): string;
export declare function nodeEqual(a: RailroadNode, b: RailroadNode): boolean;