Precisely. PHP has tools for this too, but lack the syntax. Right now you need to to all typings in comments, and thats just as bad as jsdoc was in 2005.
This could be the way PHP could go, they just need the lexer to handle types, and not do any runtime checking at all.
But i guess that goes against what the php devs want, but it sounds so wasteful, to typecheck the same code time after time even if it passed some sort of initial "compile time step".
The current amount of typechecking might be a net efficiency improvement AFAIK. It provides a hard runtime guarantee that variables are certain types while Python has to check whether something is supported at the last possible moment. But I don't know how much use the optimizer makes of that.
Python is not (usually) run like PHP. Python programs (like most other languages) "run", compared to PHP where you in 99% of all cases instead "execute". (run = the program is running for a long period of time, and execute = run/die immediately).
This subtle difference has huge implications. You could in theory have an "compile step" in. Python, but in PHP you really cant as the program is never "running".
Python built syntax for types / generics etc. Its actually a quite capable typesystem (im not a python developer, but use python on some occasions). Python then has tools for static typechecking that can be run outside execution.
This means that if python would do actual static typechecking on runtime it would be nothing more than wasted cpu cycles.
Thats why python opted for the syntax only, as its basically zero cost. In php land the typechecking is done on EVERY execution, even if the code was unused. (a void functions that has an int param, but gets passed an string, that just discards the parameter). Even worse, a type error thats not executed wont be caught by every execution.
In short PHP typesystem is just runtime checks for primitives / classes and wont catch errors where not executed. Its like the worst of both worlds.
This could be the way PHP could go, they just need the lexer to handle types, and not do any runtime checking at all.
But i guess that goes against what the php devs want, but it sounds so wasteful, to typecheck the same code time after time even if it passed some sort of initial "compile time step".