contracts in interfaces: do they work, do I have to do something to enable checking of contracts ?

[Alex]

On Monday, 1 October 2018 at 13:49:53 UTC, Emil wrote:
> I am trying my hand at contracts and they work fine in plain 
> functions and in methods, but I can't make them work in 
> interfaces.
>
> https://dlang.org/spec/interface.html#interface-contracts
>
> $ dmd --version
> DMD64 D Compiler v2.081.1
> Copyright (C) 1999-2018 by The D Language Foundation, All 
> Rights Reserved written by Walter Bright
>
>
> /////////////////////////
> void main()
> {
>     WillBloop test = new WillBloop();
>     // also tried
>     // Blooper test = new WillBloop();
>     // it compiles but the in contract does not seem enforced
>     test.limited(-1); // this does not croak
>
>     auto no_interface = new NoInterface();
>     no_interface.limited(-10); // this works as expected
> }
>
> interface Blooper
> {
>     void limited(int some_other_name)
>     in
>     {
>         assert(some_other_name > 0, "asssert failed in 
> interface");
>     }
> }
>
> class WillBloop : Blooper
> {
>     void limited(int a_name)    {
>         import std.stdio : writeln;
>         writeln(a_name);
>     }
> }
>
> class NoInterface
> {
>     void limited(int another_name)
>     in
>     {
>         assert(another_name > 0, "assert failed in 
> NoInterface");
>     }
>     do
>     {
>         import std.stdio: writeln;
>         writeln(another_name);
>     }
> }

Yeah... had such problems too, a while ago.

https://forum.dlang.org/thread/sadsceubvapbeezjytdp@forum.dlang.org

Seems, that one of the tickets is closed, but the pull request is 
not merged. Don't know how matters stand with this, actually.