cnp: save point

Now we need to implement predicates, in order to have practical
applications.

1 files changed, 25 insertions, 1 deletions

diff --git a/src/dfa.c b/src/dfa.c
index e3bcdf0..fb67047 100644
--- a/src/dfa.c
+++ b/src/dfa.c
@@ -59,12 +59,15 @@ void
 destroy_dfa(dfa *table)
 {
   /* function pointers need no destructors */
-  if (table->type == DFA_TYPE_SPECIAL) return;
+  if (table->type == DFA_TYPE_SPECIAL) goto free_last;
 
   for (int i = 0; i < table->data.table.row_n;)
     free(*(table->data.table.table+i++));
 
   free(table->data.table.table);
+
+ free_last:
+
   free(table);
 }
 
@@ -690,3 +693,24 @@ run_dfa(const dfa * const restrict table, const NUM code)
 
   return 0;
 }
+
+P_ATTR
+static BOOL
+dfa_any_fun(const NUM UNUSED code) { return 1; }
+
+dfa *
+dfa_from_func(special_dfa func)
+{
+  dfa *result = NULL;
+  SAFE_MALLOC(dfa, result, 1, return NULL;);
+  result->type = DFA_TYPE_SPECIAL;
+  result->data.fn = func;
+
+  return result;
+}
+
+dfa *
+dfa_any(void)
+{
+  return dfa_from_func(dfa_any_fun);
+}