On Monday, 4 February 2013 at 14:25:10 UTC, Timon Gehr wrote:
On 02/04/2013 03:05 PM, Andrei Alexandrescu wrote:
...
Couldn't AddressOf use "&(" + exp + ")"?
I thought more about this. The problem remains even without
@property,
due to optional parens in function invocation. Consider:
ref int fun() { ... }
auto p1 = &fun;
auto p2 = &(fun);
auto p3 = &(fun());
What are the types of the three? The optional parens in
invocation
require some disambiguation.
The obvious rule is not to give significance to redundant
parentheses.
I think the sensible disambiguation is to
have &fun take the address of fun and the other two take the
address of
fun's result.
No! &fun and &(fun) are the same thing. Functions that get
their address taken are not implicitly invoked. (Again, Scala
agrees.)
Scala don't really agree. fun is the function pointer. It is
evaluated if the function pointer is a NOOP, but that's it. Here
is scala semantic with D syntax :
void bar() {}
bar; // execute bar. Is an exception because taking the function
pointer is a NOOP.
void foo(void function() bar) {}
foo(bar); // OK, bar is not evaluated.
