diff --git a/code/src/tokenizer.c b/code/src/tokenizer.c
index 1f59cfc..6ddcd31 100644
--- a/code/src/tokenizer.c
+++ b/code/src/tokenizer.c
@@ -99,7 +99,7 @@ pac_tlist_s pac_tokenize_grammar(char *source, usz_t len_source)
                 ++offset;
                 subject                         = source[offset];
                 
-                if(!pac_rune_is_letter(subject) && (subject != '_'))
+                if(!pac_rune_is_letter(subject) && !pac_rune_is_digit(subject) && (subject != '_'))
                 {
                     break;
                 }