On Thu, Feb 21, 2019 at 9:56 AM L. David Baron <dba...@dbaron.org> wrote:
> On Thursday 2019-02-21 15:44 +0100, Andy Wingo wrote: > > ## Support in other browser / JS engines > > > > Chrome / V8 implements the draft spec. > > > > Safari / JavaScriptCore has a partial implementation that is being > > completed on an ongoing basis by Caio Lima. > > Have either of them announced plans to ship (or actually shipped) > this feature? > Chrome has been shipping for a while, and Safari has committed to shipping. The way TC39 works, the feature would not have reached stage 3 if not all big browser implementers were committed to shipping. > > (What's the opinion of TC39 on shipping features that are at stage > 3? That doesn't seem obvious from > https://tc39.github.io/process-document/ .) > As Jeff said in his reply, stage 3 is where things start to become shippable. In fact, stage 4 can only be reached if there are two shipping implementations. (Though what counts as a shipping implementation depends on the kind of feature, and is ultimately at the committee's discretion.) Stage 3 is the least-well defined of the stages—intentionally so. This is because there are requirements for the process that are at tension: - For some features, the design has to be verified through implementation in a high-performance engine, instead of just a cross-compiler or research implementation. Since a high-performance implementation of many features is an order of magnitude more effort than a straight-forward by-the-spec implementation, this usually only happens after design has otherwise completed—i.e. at stage 3. At the same time, there must be a way to take their feedback into consideration, meaning a way to reconsider the design. In which case it'd be unwise for another browser to ship the same feature. - For other features, web compatibility has to be verified. Attempting to ship is really the only way to do this in the general case, so it has to be permissible before the proposal is considered final. Till _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
