From fd6ccbb59278498d2fb0857653d8b8135c380bfa Mon Sep 17 00:00:00 2001
From: "Jurgen J. Vinju" <Jurgen.Vinju@cwi.nl>
Date: Thu, 9 Jan 2025 11:56:51 +0100
Subject: [PATCH] fixed nasty bug in Type.intersection w.r.t. parameter types

---
 src/org/rascalmpl/types/NonTerminalType.java | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/org/rascalmpl/types/NonTerminalType.java b/src/org/rascalmpl/types/NonTerminalType.java
index 20094a487ef..8ff2293f257 100644
--- a/src/org/rascalmpl/types/NonTerminalType.java
+++ b/src/org/rascalmpl/types/NonTerminalType.java
@@ -346,6 +346,9 @@ public boolean intersects(Type other) {
 		if (other == RascalValueFactory.Tree) {
 			return true;
 		}
+		else if (other.isParameter()) {
+			return other.intersects(this);
+		}
 		else if (other instanceof NonTerminalType) {
 			return ((NonTerminalType) other).intersectsWithNonTerminal(this);
 		}