feat: update

Co-authored-by: Hyeseong Kim <hey@hyeseong.kim>

Author: gwansikk

compiler/syntax/src/res_core.ml

@@ -2138,6 +2138,27 @@ and parse_operand_expr ~context p =
     (* pexp_loc = mkLoc startPos endPos *)
   }
 
+and parse_shift_operator (p : Parser.t) =
+  let start_pos = p.start_pos in
+  let end_pos = p.end_pos in
+  if p.token = LessThan && Scanner.is_left_shift p.scanner start_pos.pos_cnum
+  then (
+    Parser.next p;
+    {p with token = LeftShift; start_pos; prev_end_pos = end_pos})
+  else if
+    p.token = GreaterThan
+    && Scanner.is_right_shift_unsigned p.scanner start_pos.pos_cnum
+  then (
+    Parser.next p;
+    Parser.next p;
+    {p with token = RightShiftUnsigned; start_pos; prev_end_pos = end_pos})
+  else if
+    p.token = GreaterThan && Scanner.is_right_shift p.scanner start_pos.pos_cnum
+  then (
+    Parser.next p;
+    {p with token = RightShift; start_pos; prev_end_pos = end_pos})
+  else p
+
 (* a binary expression is an expression that combines two expressions with an
  * operator. Examples:
  *    a + b
@@ -2150,6 +2171,11 @@ and parse_binary_expr ?(context = OrdinaryExpr) ?a p prec =
     | None -> parse_operand_expr ~context p
   in
   let rec loop a =
+    let p =
+      match p.token with
+      | LessThan | GreaterThan -> parse_shift_operator p
+      | _ -> p
+    in
     let token = p.Parser.token in
     let token_prec =
       match token with
@@ -2179,6 +2205,11 @@ and parse_binary_expr ?(context = OrdinaryExpr) ?a p prec =
       Parser.leave_breadcrumb p (Grammar.ExprBinaryAfterOp token);
       let start_pos = p.start_pos in
       Parser.next p;
+      (* let p =
+        match p.token with
+        | LessThan | GreaterThan -> parse_shift_operator p
+        | _ -> p
+      in *)
       let end_pos = p.prev_end_pos in
       let token_prec =
         (* exponentiation operator is right-associative *)

compiler/syntax/src/res_scanner.ml

@@ -887,24 +887,23 @@ let rec scan scanner =
         next scanner;
         Token.Plus)
     | '>' -> (
-      match (peek scanner, peek2 scanner) with
-      | '>', '>' when not (in_diamond_mode scanner) ->
-        next3 scanner;
-        Token.GreaterThanGreaterThanGreaterThan
-      | '>', _ when not (in_diamond_mode scanner) ->
-        next2 scanner;
-        Token.GreaterThanGreaterThan
-      | '=', _ when not (in_diamond_mode scanner) ->
+      match peek scanner with
+      | '=' when not (in_diamond_mode scanner) ->
         next2 scanner;
         Token.GreaterEqual
       | _ ->
         next scanner;
         Token.GreaterThan)
-    | '<' when not (in_jsx_mode scanner) -> (
+    | '<' when not (in_diamond_mode scanner) -> (
       match peek scanner with
-      | '<' ->
+      | '=' ->
         next2 scanner;
-        Token.LessThanLessThan
+        Token.LessEqual
+      | _ ->
+        next scanner;
+        Token.LessThan)
+    | '<' when not (in_jsx_mode scanner) -> (
+      match peek scanner with
       | '=' ->
         next2 scanner;
         Token.LessEqual
@@ -1037,9 +1036,6 @@ let reconsider_less_than scanner =
   if scanner.ch == '/' then
     let () = next scanner in
     Token.LessThanSlash
-  else if scanner.ch == '<' then (
-    next scanner;
-    Token.LessThanLessThan)
   else Token.LessThan
 
 (* If an operator has whitespace around both sides, it's a binary operator *)
@@ -1058,3 +1054,26 @@ let is_binary_op src start_cnum end_cnum =
       || is_whitespace (String.unsafe_get src end_cnum)
     in
     left_ok && right_ok)
+
+let is_left_shift scanner _start_cnum =
+  (* print_endline ("@@@@@ is_left_shift ch: " ^ (Char.escaped scanner.ch)); *)
+  (* print_endline ("@@@@@ is_left_shift cnum: " ^ (string_of_int _start_cnum)); *)
+  (* print_endline ("@@@@@ is_left_shift peek: " ^ (Char.escaped (peek scanner))); *)
+  match scanner.ch with
+  | '<' -> true
+  | _ -> false
+
+let is_right_shift scanner _start_cnum =
+  (* print_endline ("@@@@@ is_right_shift ch: " ^ (Char.escaped scanner.ch)); *)
+  (* print_endline ("@@@@@ is_right_shift cnum: " ^ (string_of_int _start_cnum)); *)
+  (* print_endline ("@@@@@ is_right_shift peek: " ^ (Char.escaped (peek scanner))); *)
+  match scanner.ch with
+  | '>' -> true
+  | _ -> false
+
+let is_right_shift_unsigned scanner _start_cnum =
+  (* print_endline ("@@@@@ is_right_shift_unsigned ch: " ^ (Char.escaped scanner.ch)); *)
+  (* print_endline ("@@@@@ is_right_shift_unsigned peek: " ^ (Char.escaped (peek scanner))); *)
+  match (scanner.ch, peek scanner) with
+  | '>', '>' -> true
+  | _ -> false

compiler/syntax/src/res_scanner.mli

@@ -26,6 +26,10 @@ val scan : t -> Lexing.position * Lexing.position * Res_token.t
 
 val is_binary_op : string -> int -> int -> bool
 
+val is_left_shift : t -> int -> bool
+val is_right_shift : t -> int -> bool
+val is_right_shift_unsigned : t -> int -> bool
+
 val set_jsx_mode : t -> unit
 val set_diamond_mode : t -> unit
 val pop_mode : t -> mode -> unit

compiler/syntax/src/res_token.ml

@@ -52,10 +52,7 @@ type t =
   | ColonGreaterThan
   | GreaterThan
   | LessThan
-  | LessThanLessThan
   | LessThanSlash
-  | GreaterThanGreaterThan
-  | GreaterThanGreaterThanGreaterThan
   | Hash
   | HashEqual
   | Assert
@@ -101,6 +98,9 @@ type t =
   | Try
   | DocComment of Location.t * string
   | ModuleComment of Location.t * string
+  | LeftShift
+  | RightShift
+  | RightShiftUnsigned
 
 let precedence = function
   | HashEqual | ColonEqual -> 1
@@ -110,13 +110,12 @@ let precedence = function
   | Equal | EqualEqual | EqualEqualEqual | LessThan | GreaterThan | BangEqual
   | BangEqualEqual | LessEqual | GreaterEqual | BarGreater ->
     5
-  | Plus | PlusDot | Minus | MinusDot | PlusPlus | LessThanLessThan
-  | GreaterThanGreaterThan | GreaterThanGreaterThanGreaterThan ->
-    6
-  | Asterisk | AsteriskDot | Forwardslash | ForwardslashDot | Percent -> 7
-  | Exponentiation -> 8
-  | MinusGreater -> 9
-  | Dot -> 10
+  | LeftShift | RightShift | RightShiftUnsigned -> 6
+  | Plus | PlusDot | Minus | MinusDot | PlusPlus -> 7
+  | Asterisk | AsteriskDot | Forwardslash | ForwardslashDot | Percent -> 8
+  | Exponentiation -> 9
+  | MinusGreater -> 10
+  | Dot -> 11
   | _ -> 0
 
 let to_string = function
@@ -170,10 +169,7 @@ let to_string = function
   | HashEqual -> "#="
   | GreaterThan -> ">"
   | LessThan -> "<"
-  | LessThanLessThan -> "<<"
   | LessThanSlash -> "</"
-  | GreaterThanGreaterThan -> ">>"
-  | GreaterThanGreaterThanGreaterThan -> ">>>"
   | Asterisk -> "*"
   | AsteriskDot -> "*."
   | Exponentiation -> "**"
@@ -220,6 +216,9 @@ let to_string = function
   | Try -> "try"
   | DocComment (_loc, s) -> "DocComment " ^ s
   | ModuleComment (_loc, s) -> "ModuleComment " ^ s
+  | LeftShift -> "<<"
+  | RightShift -> ">>"
+  | RightShiftUnsigned -> ">>>"
 
 let keyword_table = function
   | "and" -> And