On 03-05-2012 20:29, Alex Rønne Petersen wrote:
On 03-05-2012 19:36, Steven Schveighoffer wrote:
On Thu, 03 May 2012 13:03:34 -0400, Kagamin <[email protected]> wrote:
On Thursday, 3 May 2012 at 14:04:41 UTC, bearophile wrote:
[p.21]
The compiler decides if it has to be passed by reference of copy
procedure Do_Something
(P1 : in Huge_Structure) –- Passed by reference if too big
D offers more low-level knowlege/control here, it doesn't decide to
pass by value or reference, leaving the decision to the programmer, I
prefer D here.
But in D code like this, where a large value is passed, I'd like the
D compiler to give a warning (despite once in a while that's exactly
what you want?):
alias int[1_000] TA;
void int(TA a) {}
I was surprised a little when compiler rejected `ref in`.
in is synonymous for "const scope".
Doing "const scope ref" yields:
"scope cannot be ref or out"
which makes sense. Just use const instead.
-Steve
Doesn't make sense to me. It seems perfectly normal to do something like
this:
void foo(ref in int i)
{
i = 42; // we're setting i indirectly, and not leaking it
}
int i;
foo(i);
On second thought, the 'const' in the 'in' would probably make this
nonsensical. Still, passing structs by ref is a case where 'ref in'
makes sense (e.g. matrices).
--
- Alex
