diff --git a/docs/grammar/SolidityParser.g4 b/docs/grammar/SolidityParser.g4
index 92718b975..3629a742d 100644
--- a/docs/grammar/SolidityParser.g4
+++ b/docs/grammar/SolidityParser.g4
@@ -311,11 +311,16 @@ errorDefinition:
 	LParen (parameters+=errorParameter (Comma parameters+=errorParameter)*)? RParen
 	Semicolon;
 
+/**
+ * User type operators.
+ */
+userOp: Add | Sub | Mul | Div | Mod | BitAnd | BitOr | BitXor | BitNot | Equal | NotEqual | LessThan | GreaterThan | LessThanOrEqual | GreaterThanOrEqual;
+
 /**
  * Using directive to bind library functions and free functions to types.
  * Can occur within contracts and libraries and at the file level.
  */
-usingDirective: Using (identifierPath | (LBrace identifierPath (Comma identifierPath)* RBrace)) For (Mul | typeName) Global? Semicolon;
+usingDirective: Using (identifierPath (As userOp)? | (LBrace identifierPath (As userOp)? (Comma identifierPath (As userOp)?)* RBrace)) For (Mul | typeName) Global? Semicolon;
 /**
  * A type name can be an elementary type, a function type, a mapping type, a user-defined type
  * (e.g. a contract or struct) or an array type.