diff --git a/core/resolver.cc b/core/resolver.cc
index 80e540b2..bb0807a8 100644
--- a/core/resolver.cc
+++ b/core/resolver.cc
@@ -101,6 +101,7 @@ void Resolver::visit(FunctionDecl* node)
 
 	Value* fval = new Value;
 	fval->setObj(CLEVER_FUNC_TYPE, func);
+	fval->setConst(true);
 
 	if (m_class && !node->isAnonymous()) {
 		func->setContext(m_class);
diff --git a/tests/lang/class_007.test b/tests/lang/class_007.test
new file mode 100644
index 00000000..712418fb
--- /dev/null
+++ b/tests/lang/class_007.test
@@ -0,0 +1,14 @@
+[FATAL] Testing member overwrite
+==CODE==
+import std.io;
+
+class Test {
+    function method() {
+        io:println('aa');
+    }
+}
+
+var w = Test.new;
+w.method = 'aaa';
+==RESULT==
+Fatal error: Cannot assign to a const variable! on \S+ line 10