Add reserved words

[ddickstein]

Tree-sitter now supports reserved keywords for better error recovery. This commit updates the OCaml grammar to mark reserved words. For example, before

let x =

type t = int

was parsed as

(compilation_unit ; [0, 0] - [4, 0]
  (value_definition ; [0, 0] - [2, 12]
    "let" ; [0, 0] - [0, 3]
    (let_binding ; [0, 4] - [2, 12]
      pattern: (value_name) ; [0, 4] - [0, 5]
      "=" ; [0, 6] - [0, 7]
      body: (infix_expression ; [2, 0] - [2, 12]
        left: (application_expression ; [2, 0] - [2, 6]
          function: (value_path ; [2, 0] - [2, 4]
            (value_name)) ; [2, 0] - [2, 4]
          argument: (value_path ; [2, 5] - [2, 6]
            (value_name))) ; [2, 5] - [2, 6]
        operator: (rel_operator) ; [2, 7] - [2, 8]
        right: (value_path ; [2, 9] - [2, 12]
          (value_name)))))) ; [2, 9] - [2, 12]

and now it is parsed as

(compilation_unit ; [0, 0] - [4, 0]
  (value_definition ; [0, 0] - [0, 5]
    "let" ; [0, 0] - [0, 3]
    (let_binding ; [0, 4] - [0, 5]
      pattern: (value_name))) ; [0, 4] - [0, 5]
  (ERROR ; [0, 6] - [0, 7]
    "=") ; [0, 6] - [0, 7]
  (type_definition ; [2, 0] - [2, 12]
    "type" ; [2, 0] - [2, 4]
    (type_binding ; [2, 5] - [2, 12]
      name: (type_constructor) ; [2, 5] - [2, 6]
      "=" ; [2, 7] - [2, 8]
      equation: (type_constructor_path ; [2, 9] - [2, 12]
        (type_constructor))))) ; [2, 9] - [2, 12]

[ddickstein]

List of reserved words taken from https://ocaml.org/manual/5.3/lex.html#sss:keywords

[aryx]

nice!

[314eter]

I was working on this myself at 314eter/tree-sitter-ocaml. But the tests are failing because the Python bindings don't support 0.25 yet, so I was waiting on that to get released to create a PR.

Some things I did that are missing here:

• Upgraded the dependencies to tree-sitter 0.25
• Excluded the nonrec keyword. It's new since OCaml 4.02, so old code may be using it as a variable.
• Included the binary operators or, lor, lxor, mod, land, lsl, lsr and asr by making them tokens in the grammar.
• Used a different set of keywords for attribute_id.

[ddickstein]

Oh okay - should I close this PR then?

…

On Mon, Apr 21, 2025 at 10:54 AM Pieter Goetschalckx < ***@***.***> wrote: I was working on this myself at 314eter/tree-sitter-ocaml <https://github.com/314eter/tree-sitter-ocaml/tree/tree-sitter-0.25>. But the tests are failing because the Python bindings don't support 0.25 yet <tree-sitter/py-tree-sitter#333>, so I was waiting on that to get released to create a PR. Some things I did that are missing here: - Upgraded the dependencies to tree-sitter 0.25 - Excluded the nonrec keyword. It's new since OCaml 4.02, so old code may be using it as a variable. - Included the binary operators or, lor, lxor, mod, land, lsl, lsr and asr by making them tokens in the grammar. - Used a different set of keywords for attribute_id. — Reply to this email directly, view it on GitHub <#117 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAGD5T5QZAWMEKAEYQU2TID22UBCBAVCNFSM6AAAAAB3QJUKFSVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQMJYGY3DMMZYGQ> . You are receiving this because you authored the thread.Message ID: ***@***.***> *314eter* left a comment (tree-sitter/tree-sitter-ocaml#117) <#117 (comment)> I was working on this myself at 314eter/tree-sitter-ocaml <https://github.com/314eter/tree-sitter-ocaml/tree/tree-sitter-0.25>. But the tests are failing because the Python bindings don't support 0.25 yet <tree-sitter/py-tree-sitter#333>, so I was waiting on that to get released to create a PR. Some things I did that are missing here: - Upgraded the dependencies to tree-sitter 0.25 - Excluded the nonrec keyword. It's new since OCaml 4.02, so old code may be using it as a variable. - Included the binary operators or, lor, lxor, mod, land, lsl, lsr and asr by making them tokens in the grammar. - Used a different set of keywords for attribute_id. — Reply to this email directly, view it on GitHub <#117 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAGD5T5QZAWMEKAEYQU2TID22UBCBAVCNFSM6AAAAAB3QJUKFSVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQMJYGY3DMMZYGQ> . You are receiving this because you authored the thread.Message ID: ***@***.***>