diff --git a/bnf/Dsp.g4 b/bnf/Dsp.g4
index dac731c..fd2784b 100644
--- a/bnf/Dsp.g4
+++ b/bnf/Dsp.g4
@@ -13,7 +13,7 @@ term
     : SYMBOL                                                 # symbol
     | '(' term ')'                                           # parentheses
     | term '::' term                                         # binary
-    | term '.' term                                          # binary
+    | term ('.' | '->') term                                 # binary
     | term '[' term (',' term)* ']'                          # subscript
     | term '(' (term (',' term)*)? ')'                       # function
     | <assoc=right> ('~' | '!' | '-' | '+' | '&' | '*') term # unary