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.)
The rules are straightforward:
A non-@property function name 'foo' denotes a function invocation
without arguments iff it does not occur in one of the following contexts:
1. foo(...) // explicitly called
2. &foo // address taken
3. ...!(...,foo,...) // template argument (well, that's what DMD
currently does)
4. alias ... = foo; // aliased
I would agree restricting the properties, but requiring a __trait to
take the address of a regular function or method seems overkill.
I have no idea how the conclusion would be reached that this is
necessary under any of the discussed schemes.
