alt Hacker NewsSo for interpreted languages with types that are written in C, how is the engine supposed to tell C it already checked all the arg types manually in the interpreter? In other words: it's safe to go ahead and dereference this function and invoke it with these args.
Seems like C technically requires function declarations for every possible signature. That quickly explodes into hundreds or thousands of function declarations in the header and switch statement.
Edit: clarification
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pizlonator • yesterday at 10:07 PM
I’ve thought about how to let folks prove to Fil-C that Fil-C’s checks are obviated by some higher level checks.
It’s a super hard problem! I don’t have a good answer, but I also can’t prove that it’s impossible
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If you have an interpreted language, you don't have a C function corresponding to each language function. You have a C interpreter loop with a "current instruction" pointer. When the current interpreted instruction is a call, you check all the things you need to check, push the current IP to a stack, and set the IP to the first instruction of the function.
C's type checker never sees the interpreted language's functions.