test/check_cnp: working algorithm

I now have a working algorithm in test/check_cnp.  It can correctly
parse the grammar for an esoteric language called "Brainfuck".  This
language does not matter.  What matters is that it contains
parentheses.  So this shows that at least for grammars as complex as
parentheses, this parser works well.  Haha.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/list.h b/src/list.h
index 76dde0a..33bdf3e 100644
--- a/src/list.h
+++ b/src/list.h
@@ -45,7 +45,7 @@ void *copy_num(void *);
 /* upon failure return 1 */
 BOOL copy_list(List *dest, List *source, copyer copyf);
 
-void *list_nth(const List * const ls, NUM n);
+void *list_nth(CCR_MOD(List *) ls, NUM n);
 
 NUM list_length(const List * const restrict ls);