Rejected by tc39 on Nov 2023.
try { return JSON.parse(str) } catch { return undefined }
JSON.parse ( _text_ [ , _reviver_ ] )
1. Let _result_ be Completion(Call(%JSON.parse%, *null*, << _text_, _reviver_ >> )).
1. If _result_ is an abrupt completion, return *undefined*.
1. Return _result_.