Hello, to play the devils advocate: why does JavaScript need static typing?
Your proposal doesn't really answer that. Sure, it mentions tooling and IDEs that can provide you with type hints and complain on mistakes, but things like Flow and Typescript do this today already. What's your goal, to have JS engines run Typescript(-like) code natively without transpiling? For backwards-compatibility you'd have to do that anyway, especially if new type system features are introduced incrementally. What's the point of building this feature into engines? It just provides additional complexity. Not to mention the difficulty of finding a suitable type system that is both sophisticated enough to describe all useful code (not taking away too much flexibility) and simple enough to understand without a CS degree. And which interfaces well with un-typed completely dynamic code. What does "static typing" even mean to you in a dynamic scripting language? JavaScript is not compiled by the developer, it is run by the user. Where (when) do you expect types to be checked? Should the engine throw early errors (during parsing)? During parsing of which parts of the code, even when "normal" (untyped) code is calling into typed code? Or do you expect dynamic runtime errors, like when assigning an invalid value to a "typed variable" or calling a "typed function" with wrong arguments? Are type definitions completely constant or could they be mutated/extended/etc dynamically (and what happens when you introduce new types with `eval` or by loading another script)? A proposal would need to provide an objective that answers all these questions, before even considering any particular type system or syntax. One way to go forward that I can see would be a proposal that reserves a relatively unrestricted syntax for type annotations (which are already considered during every grammar amendment anyway, for compatibility with Flow/Typescript), but not assign any semantics to them and require engines to simply ignore them. External tooling could then use these annotations according to its own rules. kind regards, Bergi _______________________________________________ es-discuss mailing list es-discuss@mozilla.org https://mail.mozilla.org/listinfo/es-discuss
