Method getDeltaToAncestor

src/org/antlr/codebuff/Trainer.java:491–500

Return the number of hops to get to ancestor from node or -1 if we don't find ancestor on path to root.

(ParserRuleContext node, ParserRuleContext ancestor)

	 *  don't find ancestor on path to root.
	 */
	public static int getDeltaToAncestor(ParserRuleContext node, ParserRuleContext ancestor) {
		int n = 0;
		ParserRuleContext p = node;
		while ( p!=null && p!=ancestor ) {
			n++;
			p = p.getParent();
		}
		if ( p==null ) return -1;
		return n;
	}

	public static ParserRuleContext getAncestor(ParserRuleContext node, int delta) {
		int n = 0;