C `restrict` keyword in D

[jmh530 via Digitalmars-d]

On Sunday, 3 September 2017 at 03:04:58 UTC, Uknown wrote:
> I just hope to have a nice discussion on this topic here.
>
> Thanks!
>

You might find interesting the reference capabilities of Pony:
https://tutorial.ponylang.org/capabilities/reference-capabilities.html

So with respect to restrict, there are a few that might be 
relevant.

iso - can only have one reference
box - similar to const function parameters in D, can give out 
read-only views
trn - sort of the reverse of const, it's like a write unique, you 
can write to, but other people cannot

When I think of restrict, it's like telling the compiler that 
these two pointers don't overlap their data. By contrast, if you 
pass parameters to a function with these reference capabilities, 
then it would be providing the compiler slightly different 
information. If you pass iso, it tells the compiler that no other 
variable pointers to this variable. If you use box (const), 
you're telling the compiler that you won't modify it in this 
function. If you use trn, you're telling the compiler that this 
reference is the only way to modify the variable (i.e. another 
variable in the function cannot modify it).

I'm not an expert on pony or anything, so I'm not sure how 
complicated this makes things with aggregate types.