Re: [PHP-DEV] [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