On Friday, 30 September 2016 at 00:05:45 UTC, Steven
Schveighoffer wrote:
On 9/29/16 7:42 PM, Jacob wrote:
Was wondering if this feature could be implemented, right now
auto needs
to be written like this:
auto pValue = someFunctionReturnsRef(); // forgot '&',
still valid
// makes a copy
when we
didn't want one
The feature would make the code look like this:
auto* pValue = someFunctionReturnsRef(); // error
expecting pointer
We don't accidentally make a copy when we wanted a pointer.
C++ has a
similar semantic for it's auto.
Hm... I'm not familiar with C++ auto, but C++ does have local
references. D does not.
I'm not sure if you are asking for the syntax specified, or
asking for the original line to be treated like the specified
syntax. The latter absolutely is not going to happen, because
that breaks valid code.
Even if we added:
auto* pValue = expr;
I don't see why this is more advantageous than:
auto pValue = &expr;
-Steve
auto* pValue = expr; // still invalid code unless expr evaluate
to a pointer type
auto* pValue = &expr; // this is valid if expr is a ref
It still requires the &, what it prevents is this situation:
auto pValue = expr; // wanted pointer, expr evaluates to non-ptr
value through change of code or simply forgetting "&"
So no code should be broken, you can do everything the same way
without a change in behavior and auto with a "*" is currently
invalid.
Basically how it works in C++: http://ideone.com/TUz9dO
