bugfix: symbol got overwritten

1 files changed, 2 insertions, 0 deletions

diff --git a/neb/__init__.py b/neb/__init__.py
index bfbea19..b48b8f9 100644
--- a/neb/__init__.py
+++ b/neb/__init__.py
@@ -26,6 +26,8 @@ def syntaxFunc(symbol, env, ns):
             if isinstance(env_func, MultiFunction):
                 env_func.register(func)
                 env.register(symbol.name, env_func)
+            else:
+                raise InterpretPanic(symbol, "not a multifunc!")
         else:
             mf = MultiFunction(symbol.name)
             mf.register(func)