On Tuesday, 30 December 2014 at 16:25:05 UTC, Steven
Schveighoffer wrote:
On 12/30/14 10:51 AM, Dicebot wrote:
On Tuesday, 30 December 2014 at 15:48:03 UTC, Steven
Schveighoffer wrote:
On 12/18/14 11:54 AM, Dicebot wrote:
I wasn't subscribed to druntime changes thus missed this
discussion.
Will chime in there soon.
Ping, still waiting on this :)
*blush*
OK, I see your response, but I'm still curious as to
how/whether your DIP would solve it. Any thoughts on the
feature brought up in this thread?
-Steve
In this specific case I actually expected this to work:
struct S
{
int key, value;
import std.typetuple;
alias asTuple = TypeTuple!(this.tupleof);
alias asTuple this;
}
void main()
{
S s;
s[0] = 42;
}
However it does not seem to recognize that `this` pointer is
available in such specific invocation. It can be a bug or there
may be a legitimate reason preventing it - not entirely sure.
Unfortunately I have never completely understood cases when alias
is able to preserve context pointer and when it can't.
If it worked though, my proposal would allow more customized
access:
struct S
{
int x;
template MyTuple()
{
alias opIndex(size_t i) = S.x;
}
alias MyTuple this; // note it is not MyTuple!()
}
void main()
{
S s;
s[100] = 42;
assert(s[50] == 42);
}
It is not exactly the thing you were originally looking for but I
am against any attempt to try adding template argument list
flavor to "normal" aggregates - it creates many new corner cases
to consider. One example was mentioned in DIP - if `static
opIndex` is the thing why can't you do S[0] but only s[0]? It is
static after all! More tricky stuff to explain - not worth the
feature in my opinion.
