package ppx_js_style

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Code style checker for Jane Street Packages


Dune Dependency





ppx_js_style - Enforce Jane Street coding styles

ppx_js_style is an identity ppx rewriter that enforces Jane Street coding styles.

Coding rules

The following rules are enforced by ppx_js_style:

  • Enabled by -dated-deprecation: [@@deprecated] attributes must contain the date of deprecation, using the format "[since MM-YYYY] ..." N.B. this check, on by default at janestreet, but off by default externally, can also be disabled with the flag -no-dated-deprecation

  • Enabled by -annotated-ignores: Ignored expressions must come with a type annotation, such as: ignore (expr : typ) let _ : type = expr Note that aliases need not be annotated: let _ = in

  • Enabled by -check-doc-comments: Comments in mli must either be documentation comments or explicitely "ignored": (** documentation comment *) (*_ ignored comment *) Normal (* comment *) comments are disallowed.

    This flag additionally enables warning 50, which checks the placement of documentation comments.

    Finally, doc comments are checked to be syntactically valid.

  • Enabled by -compat-32: Checks that calling ocamlc on the input would produce bytecode that works on 32 bits architectures (including js_of_ocaml), ie that all constant are representable on 32 bits architectures. Compared to the compiler flag by the same name, it allows to perform this check without building any bytecode.


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