diff --git a/include/custom.h b/include/custom.h
index f58e0db..d719da9 100644
--- a/include/custom.h
+++ b/include/custom.h
@@ -29,6 +29,12 @@ struct libab_behavior_s {
  * registered with libabacus.
  */
 struct libab_operator_s {
+    /**
+     * The type of the operator (infix, prefix, postfix).
+     * Corresponds to token types associated with
+     * each operator.
+     */
+    int type;
     /**
      * The precedence of the operator.
      */
diff --git a/src/libabacus.c b/src/libabacus.c
index 5446da5..8431b0a 100644
--- a/src/libabacus.c
+++ b/src/libabacus.c
@@ -58,6 +58,7 @@ libab_result _register_operator(libab* ab, const char* op, int token_type, int p
         new_entry->data_u.op.behavior.type = NULL;
         new_entry->data_u.op.precedence = precedence;
         new_entry->data_u.op.associativity = associativity;
+        new_entry->data_u.op.type = token_type;
     } else {
         result = LIBAB_MALLOC;
     }