Re: [Pre-RFC] Opt-in JSON comments and trailing commas

On Mon, Aug 17, 2026, at 1:18 PM, Otar Chekurishvili wrote: > Hello! > > I would like to discuss a draft RFC that adds two independent and > opt-in flags to ext/json for PHP 8.7: > > - JSON_ALLOW_COMMENTS > - JSON_ALLOW_TRAILING_COMMAS > > Both flags would be accepted by json_decode() and json_validate(). > Strict JSON would remain the default. Comments are limited to // and > non-nesting /* ... */ at JSON whitespace boundaries. Trailing commas > permit one comma after the last element or member of a nonempty array > or object. > > The implementation processes comments in the existing re2c scanner. It > handles trailing commas in the existing Bison grammar. It does not > preprocess or copy the input, so it preserves strings and original > source locations. The RFC uses two primary votes so that either > extension can be accepted independently. > > Draft implementation is located here: > https://github.com/php/php-src/pull/23336 > > Recently I also published a similar PHP library: > https://github.com/otar/jsonc > > I would particularly appreciate feedback on the API names and the > inclusion of json_validate(). Feedback on the specified UTF-8, > control-character, and error-location behavior would also be useful. > > > Otar Does this essentially mean JSON5 support? If so, just call it that. (I am undecided on the best way to support that.) --Larry Garfield