JSX

You signed in with another tab or window. Reload to refresh your session. You signed out in another tab or window. Reload to refresh your session. You switched accounts on another tab or window. Reload to refresh your session. Dismiss alert The purpose of this specification is to define a concise and familiar syntax for defining tree structures with attributes. A generic but well defined syntax enables a community of independent parsers and syntax highlighters to conform to a single specification. Embedding a new syntax in an existing language is a risky venture. Other syntax implementors or the existing language may introduce another incompatible syntax extension. Through a stand-alone specification, we make it easier for implementors of other syntax extensions to consider JSX when designing their own syntax. This will hopefully allow various new syntax extensions to co-exist. It is our intention to claim minimal syntactic real estate while keeping the syntax concise and familiar. That way we leave the door open for other extensions. This specification does not attempt to comply with any XML or HTML specification. JSX is designed as an ECMAScript feature and the similarity to XML is only for familiarity. ECMAScript 6th Edition (ECMA-262) introduces template literals which are intended to be used for embedding DSL in ECMAScript. Why not just use that instead of inventing a syntax that's not part of ECMAScript? Template literals work well for long embedded DSLs. Unfortunately the syntax noise is substantial when you exit in and out of embedded arbitrary ECMAScript expressions with identifiers in scope. However, this would lead to further divergence. Tooling that is built around the assumptions imposed by template literals wouldn't work. It would undermine the meaning of template literals. It would be necessary to define how JSX behaves within the rest of the ECMAScript grammar within the template literal anyway. Another alternative would be to use object initializers (similar to JXON ). Unfortunately, the balanced braces do not give great syntactic hints for where an element starts and ends in large trees. Balanced named tags is a critical syntactic feature of the XML-style notation. The JSX syntax is similar to the E4X Specification (ECMA-357) . E4X is a deprecated specification with deep reaching semantic meaning. JSX partially overlaps with a tiny subset of the E4X syntax. However, JSX has no relation to the E4X specification. The main purpose of this repository is to continue evolving JSX. We are grateful to the community for contributing bugfixes and improvements. Meta has adopted a Code of Conduct that we expect project participants to adhere to. Please read the full text so that you can understand what actions will and will not be tolerated. Read our Contributing Guide to learn about our development process, how to propose bugfixes and improvements, and how to build and test your changes to JSX.