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Ppxlib 0.36.2

We're pleased to announce ppxlib 0.36.2, a maintenance release with two bug fixes related to OCaml 5.2 AST changes for type constraints in let bindings.

What's Fixed

Ast_builder compatibility: The value_binding constructor now automatically handles the AST migration from OCaml 4.14 to 5.2, correctly generating pvb_constraint fields when type constraints are present. This means PPX authors don't need to manually update their code for the new AST representation.

PPrintast output: Fixed pretty-printing of legacy Ppat_constraint nodes with Ptyp_poly to produce valid OCaml syntax, ensuring generated code remains compilable during the transition period.

Both fixes improve compatibility across OCaml compiler versions.

See full changelog

CHANGES:

  • Make Ast_builder's default value_binding constructor generate the proper
    pvb_constraint from the pattern and expression arguments.
    (#589, @NathanReb)
  • Fix pprintast to output correct syntax from Ppat_constraint (pat, Ptyp_poly ...)
    nodes until they are completely dropped. (#588, @NathanReb)