1 files changed, 3 insertions, 8 deletions
diff --git a/bu-parser.h b/bu-parser.h
index 7dc7034..8910b5d 100644
--- a/bu-parser.h
+++ b/bu-parser.h
@@ -7,17 +7,10 @@
 #include "tree.h"
 
 /* PRODUCTION RULES
-
-  <expr> ::= <expr> <binary_op> <expr> | <unary_op> <expr> | <var>
+  <expr> ::= <expr> <binary_op> <expr> | <unary_op> <expr> | "(" <expr> ")" | <var>
   <binary_op> ::= "*" | "+"
   <unary_op> ::= "!"
   <var> ::= r#[a-z]
-
- */
-
-/* POSSIBILITIES
-  a-z => var
-  
  */
 
 enum parser_state {
@@ -31,6 +24,8 @@ enum token_id {
   TOKEN_BINARY_OPERATOR,
   TOKEN_UNARY_OPERATOR,
   TOKEN_VARIABLE,
+  TOKEN_OPEN_PAREN,
+  TOKEN_CLOSE_PAREN,
   TOKEN_EOS,
   TOKEN_OOB,
   TOKEN_MAX,