Re: inout delegate

[Steven Schveighoffer via Digitalmars-d]

On 10/2/16 2:55 AM, Manu via Digitalmars-d wrote:
Can someone explain this to me?
class Test
{
  inout(int) f() inout { return 10; }

  void t()
  {
    f(); // calls fine with mutable 'this'
    auto d = &this.f; // error : inout method Test.f is not callable
using a mutable this
    d();
  }
}

That error message seems very unhelpful, and it's not true. Of course
an inout method is callable with a mutable 'this'...

I suspect that the problem is the type for the delegate; "inout(int)
delegate()" doesn't leave anything for the type system to resolve the
inout with.
I guess the expectation is that this delegate has it's inout-ness
resolved when you capture the delegate:
  is(typeof(&this.f) == int delegate())
Or if 'this' were const:
  is(typeof(&this.f) == const(int) delegate())

I think this is a bug, and I 100% agree with you. The type of the 
delegate should be based on the mutability of 'this'.

The error message probably stems from logic that was meant to prevent 
invalid const/immutable delegate capture, but inout wasn't thought of.

-Steve