/*!
 * Copyright 2016 The ANTLR Project. All rights reserved.
 * Licensed under the BSD-3-Clause license. See LICENSE file in the project root for license information.
 */
import { Parser } from "../../Parser";
import { ParseTree } from "../ParseTree";
import { Token } from "../../Token";
import { XPathElement } from "./XPathElement";
/**
 * Represent a subset of XPath XML path syntax for use in identifying nodes in
 * parse trees.
 *
 * Split path into words and separators `/` and `//` via ANTLR
 * itself then walk path elements from left to right. At each separator-word
 * pair, find set of nodes. Next stage uses those as work list.
 *
 * The basic interface is
 * {@link XPath#findAll ParseTree.findAll}`(tree, pathString, parser)`.
 * But that is just shorthand for:
 *
 * ```
 * let p = new XPath(parser, pathString);
 * return p.evaluate(tree);
 * ```
 *
 * See `TestXPath` for descriptions. In short, this
 * allows operators:
 *
 * | | |
 * | --- | --- |
 * | `/` | root |
 * | `//` | anywhere |
 * | `!` | invert; this much appear directly after root or anywhere operator |
 *
 * and path elements:
 *
 * | | |
 * | --- | --- |
 * | `ID` | token name |
 * | `'string'` | any string literal token from the grammar |
 * | `expr` | rule name |
 * | `*` | wildcard matching any node |
 *
 * Whitespace is not allowed.
 */
export declare class XPath {
    static readonly WILDCARD: string;
    static readonly NOT: string;
    protected path: string;
    protected elements: XPathElement[];
    protected parser: Parser;
    constructor(parser: Parser, path: string);
    split(path: string): XPathElement[];
    /**
     * Convert word like `*` or `ID` or `expr` to a path
     * element. `anywhere` is `true` if `//` precedes the
     * word.
     */
    protected getXPathElement(wordToken: Token, anywhere: boolean): XPathElement;
    static findAll(tree: ParseTree, xpath: string, parser: Parser): Set<ParseTree>;
    /**
     * Return a list of all nodes starting at `t` as root that satisfy the
     * path. The root `/` is relative to the node passed to {@link evaluate}.
     */
    evaluate(t: ParseTree): Set<ParseTree>;
}