better handling for nonExist in the C runtime. BIND is also supported in the linearizer but not in the parser yet

1 files changed, 6 insertions, 2 deletions

diff --git a/src/runtime/python/pypgf.c b/src/runtime/python/pypgf.c
index b5ff53af0..a76344ca7 100644
--- a/src/runtime/python/pypgf.c
+++ b/src/runtime/python/pypgf.c
@@ -1378,8 +1378,12 @@ Concr_linearize(ConcrObject* self, PyObject *args)
 	
 	pgf_linearize(self->concr, pyexpr->expr, out, err);
 	if (!gu_ok(err)) {
-		PyErr_SetString(PGFError, "The abstract tree cannot be linearized");
-		return NULL;
+		if (gu_exn_caught(err) == gu_type(PgfLinNonExist))
+			Py_RETURN_NONE;
+		else {
+			PyErr_SetString(PGFError, "The abstract tree cannot be linearized");
+			return NULL;
+		}
 	}
 
 	GuString str = gu_string_buf_freeze(sbuf, tmp_pool);