Re: Get UDAs of self's declaration as a member?

[Ali Çehreli via Digitalmars-d-learn]

On 4/25/22 14:32, cc wrote:
> Hard to word this question right, but is it possible to get the UDAs
> assigned to a class/structure's member variable declaration, within that
> variable's definition?  e.g.

That sounds backwards to me too. :) Policy-based design can work here:

import std.stdio;
import std.traits;

enum SPECIAL { no, yes }

struct Foo(SPECIAL special = SPECIAL.no)  {
    void foo() {
      static if (special == SPECIAL.yes)
        writeln("special");
      else
        writeln("not special");
    }
}

struct Bar {
  Foo!(SPECIAL.yes) foo;
}

alias FooSpecial = Foo!(SPECIAL.yes);
alias FooRegular = Foo!(SPECIAL.no);

void main() {
  Foo!() foo;        // <-- Without the aliases
  FooSpecial foo_;   // <-- Better syntax with aliases
  foo.foo;
  Bar bar;
  bar.foo.foo;
}

Ali