org.antlr.v4.runtime.tree.SyntaxTree Maven / Gradle / Ivy
/*
* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
* Use of this file is governed by the BSD 3-clause license that
* can be found in the LICENSE.txt file in the project root.
*/
package org.antlr.v4.runtime.tree;
import org.antlr.v4.runtime.TokenStream;
import org.antlr.v4.runtime.misc.Interval;
/** A tree that knows about an interval in a token stream
* is some kind of syntax tree. Subinterfaces distinguish
* between parse trees and other kinds of syntax trees we might want to create.
*/
public interface SyntaxTree extends Tree {
/**
* Return an {@link Interval} indicating the index in the
* {@link TokenStream} of the first and last token associated with this
* subtree. If this node is a leaf, then the interval represents a single
* token and has interval i..i for token index i.
*
* An interval of i..i-1 indicates an empty interval at position
* i in the input stream, where 0 <= i <= the size of the input
* token stream. Currently, the code base can only have i=0..n-1 but
* in concept one could have an empty interval after EOF.
*
* If source interval is unknown, this returns {@link Interval#INVALID}.
*
* As a weird special case, the source interval for rules matched after
* EOF is unspecified.
*/
Interval getSourceInterval();
}