> But instead of working the way the languages do now, instead of constantly walking through all the layers of indirection that can be used to implement all this at every call site and for every call, what if you could do something like the "pledge()" call that says "OK, this is it, I'm all set up, the dynamism is all done, you may now assume that all the type analysis you've done is now complete". Now the JIT can drop all of its paranoia code.

This sounds a lot like Object.freeze[0] in JS, at least for prototypes. I can't remember any of the major engines doing this, but it could be an interesting direction to explore.

[0]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...