import type ContextType from "./context-type.js";
export type Pending = {
    index: number;
    rollback: string;
};
export declare const last: <T>(elements: T[]) => T | undefined;
export default class Context {
    readonly type: ContextType;
    private readonly start;
    readonly tokens: string[];
    readonly pending: Pending[];
    readonly parent?: Context;
    readonly children: Context[];
    rolledBack: boolean;
    constructor(type: ContextType, parent?: Context);
    discard(): void;
    inside(context: ContextType, depth?: number): boolean;
    lookup(context: ContextType, depth?: number): Context | null;
    push(token: string, rollback?: string): void;
    rollback(recursive?: boolean): void;
}