Steven Schveighoffer wrote:
"Andrei Alexandrescu" wrote
The compiler's escape detection mechanism can't help quite a lot here
because the escape hatch is rather indirect.
Initially I thought SafeD should prevent such escapes, whereas D allows
them. Now I start thinking the pattern above is dangerous enough to be
disallowed in all of D. How about this rule?
***************
Rule: ref parameters are PASS-DOWN and RETURN only. No escaping of
addresses of ref parameters is allowed. If you want to escape the address
of a ref parameter, use a pointer in the first place.
***************
As long as there is a way to circumvent this, I'm OK with this rule.
Something that's the equivalent of a cast. Two reasons:
1. Using a * dereference pointer inside a function for all usages is
sometimes tedious. This would be a non issue if ref local variables were
allowed, i.e.:
void foo(int *x)
{
ref int rx = *x;
// use rx until you need to copy the address of x.
}
2. you may need to call functions you have no control over that take a
pointer but do not save a reference to it. e.g. system calls.
-Steve
Yah, an explicit cast ref T -> T* must be still allowed.
Andrei
