JSONvariante

JSONvariante is a data-interchange format derived from JSON, proposed by the open-source community as an informal extension to address practical needs in configuration files and APIs. It keeps the general JSON syntax but adds flexibility for developers, and it is not part of any formal international standard.

Core features of JSONvariante include optional support for comments (both inline and block), a permissive trailing comma policy, and a relaxed whitespace rule. It may also allow nonstandard numeric values such as NaN and Infinity, depending on the parser configuration. These changes aim to improve human readability and ease of editing, while preserving the basic data types of JSON: strings, numbers, booleans, null, arrays, and objects. Parsers are typically configurable to reject or tolerate nonstandard elements.

In practice, JSONvariante is used mainly in configuration files and internal APIs where developers value inline documentation and lenient syntax. Because it is not standardized, compatibility varies: standard JSON parsers fail to parse it without special options; some libraries offer modes to accept its extensions, and others provide dedicated parsers in languages like JavaScript, Python, and Java.

Example (illustrative, non-normative):

{

// server settings

"host": "example.com",

"port": 443,

"features": [ "logging", "metrics", ],

/ optional verbose mode /

"mode": "production",

"threshold": NaN,

"limit": Infinity

}

Critics argue that such deviations reduce portability and machine-readability, while supporters see improved developer experience in controlled environments. As a result, many projects choose established formats like JSON5, YAML, or plain JSON with external metadata rather than JSONvariante. Related formats include JSON, JSON5, YAML, and BSON.