Re: Ideal performance of ELisp

[Stefan Monnier]

> Once the VM supports proper tail recursion, it's straightforward to
> generate automata that never perform a function call, at least not as part
> of the recognizer.

It was straightforward beforehand as well (using a `while` loop instead
of recursion).  And if you do use recursion, then it's not very much
simpler with `lexical-binding` than without because you still have to
take into account the possibility that the function gets redefined
during your recursion :-(

Don't get me wrong: `lexical-binding` is definitely very useful for
native compilation (and it does help for tail-calls in some cases,
e.g. in `named-let`), but I suspect that for the foreseeable future
it'll stay hard to be competitive with something like tree-sitter when
writing the code in ELisp.


        Stefan