introduce namespaces
diff --git a/libasn1fix/asn1fix_retrieve.h b/libasn1fix/asn1fix_retrieve.h
index 95b8330..8143937 100644
--- a/libasn1fix/asn1fix_retrieve.h
+++ b/libasn1fix/asn1fix_retrieve.h
@@ -37,10 +37,8 @@
  * Return the reference to a destination of the given reference,
  * symbol lookup. Not a recursive function.
  */
-asn1p_expr_t *asn1f_lookup_symbol(arg_t *arg,
-		asn1p_module_t *mod,
-		asn1p_expr_t *rhs_pspecs,
-		const asn1p_ref_t *ref);
+asn1p_expr_t *asn1f_lookup_symbol(arg_t *arg, asn1p_expr_t *rhs_pspecs,
+                                  const asn1p_ref_t *ref);
 
 /*
  * Recursively find the original type for the given expression.