Is there a compile-to-Python language with built-in type safety, similar to how TypeScript transpiles to JavaScript? I'm aware of Mojo and mypyc, but those compile to native code/binaries, not Python source.
Python does not need that, as it has built-in type annotation support. The annotation is any expression, so you can in theory express anything a custom type-only language would allow you (although you could make it less verbose and easier to read).
However, the it IMHO just works much worse than TS because:
* many libraries still lack decent annotations
* other libraries are impossible to type because of too much dynamic stuff
* Python semantics are multiple orders of magnitude more complex than JavaScript.
Even just the simplest question: Is `1` allowed in parameter typed `float`? What about numpy float64?
Thanks for helping me understand. I wasn't aware of Python's type annotation support. I did some quick research and learned that type annotations don't cause compile errors even when there are type errors. Is that why type checkers like Pyrefly exist?
The only language I'm aware of that's a bit like that is rpython, but it's the other way round: designed for python to compile to it. If you think about it, you get more benefit from the typed language being the base one, as the compiler or JIT can make more assumptions, producing faster code . Typescript had no alternative but to do it the other way, since it's a lot harder to get things adopted into the browser than to ship them independently.
exyi|8 hours ago
However, the it IMHO just works much worse than TS because: * many libraries still lack decent annotations * other libraries are impossible to type because of too much dynamic stuff * Python semantics are multiple orders of magnitude more complex than JavaScript. Even just the simplest question: Is `1` allowed in parameter typed `float`? What about numpy float64?
tl2do|8 hours ago
ajb|6 hours ago
sakesun|5 hours ago