ppx: add [@json.catch_all] for forward-compatible string enums - #88
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For polymorphic and classic variants under [@@deriving json], the [@json.catch_all] attribute marks the constructor that absorbs any unknown wire tag, lossless. The constructor's argument is Melange_json.unknown_variant_case, a record with fields { tag : string; payload : Melange_json.t list option }; payload distinguishes bare strings (None) from array forms (Some xs), so the decoder captures both wire shapes and the encoder re-emits them faithfully. Pairs naturally with [@@json.compact_variants] so the known cases are bare strings. Also ships unknown_variant_case_jsonschema on the native side, structurally compatible with ppx_deriving_jsonschema_runtime.t (no hard dependency).
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* main: (40 commits) Respect nonrec type declarations in json derivers (#94) ppx/test: cover encode behavior for @drop_default variants (#84) allow @@compact_variants to parse ["Tag"] in addition to "Tag" for nullary variants (#93) Make extra JSON fields allowed by default (#92) Fix error messages for `[@@json.compact_variants]` (#91) Revert "Fix error message for @@compact_variants" (#90) Fix error message for @@compact_variants (#87) ppx: add [@json.catch_all] for forward-compatible string enums (#88) classify: filter undefined values from JS objects (#86) Add primitives semantics table to readme (#82) Support @json.compact_variants on polyvariant types (#79) ppx: allow dropping arbitrary values with `[@drop_default]` (#77) .gitignore: .claude upgrade ppxlib to 0.36 / handle Ptyp_open (#60) build with Melange 6 / OCaml 5.4 (#72) fmt: format using OCamlformat 0.28 (#75) fix: use `opam-check-npm-deps` compatible with OPAM 2.5 (#74) native: re_export yojson browser: remove dup of_json_error_to_string native: +of_json_error_to_string ...
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For polymorphic and classic variants under
[@@deriving json], the[@json.catch_all]attribute marks the constructor that absorbs any unknown wire tag, lossless. The constructor's argument isMelange_json.unknown_variant_case, a record with fields{ tag : string; payload : Melange_json.t list option }; payload distinguishes bare strings (None) from array forms (Some xs), so the decoder captures both wire shapes and the encoder re-emits them faithfully.Pairs naturally with
[@@json.compact_variants]so the known cases are bare strings.Also ships
unknown_variant_case_jsonschemaon the native side, structurally compatible withppx_deriving_jsonschema_runtime.t(no hard dependency).