alt Hacker News> the references are just an internal optimization
Optimization specifically for function calls, or... ?
Because if you're doing all this copy-on-write anyway, the indirection seems to be a needless cost in other contexts.
> the references are just an internal optimization
Optimization specifically for function calls, or... ?
Because if you're doing all this copy-on-write anyway, the indirection seems to be a needless cost in other contexts.
This applies everywhere, and it fundamentally wouldn't be possible for just function calls.
> needless cost
Are you comparing to a language with mutable references or a our functional language? A language with mutable references will of course be faster, but this is more intended as an alternative to pure functional languages (since functions are referentially transparent).
In this case, the cost of the indirection is approximately zero (relative to the cost of just doing reference counting), since passing a reference just requires a bump to the refcount. And most of the time the refcount increments are skipped by "moving" instead of copying the reference.