/+dub.sdl:

dependency "optional" version="~>0.7.1"

+/

import std.stdio;

​

import optional;

​

void main()

{

    static class C { void f() {} }

    static struct S { void f() {} }

​

    void f0(NotNull!C c) {

        c.f();

    }

​

    void f1(NotNull!(S*) sp) {

        sp.f();

    }

​

    auto c = notNull!C;

    auto sp = notNull!(S*);

​

    f0(c);

    f1(sp);

​

    static assert(!__traits(compiles, { c = null; }));

    static assert(!__traits(compiles, { sp = null; }));

    static assert(!__traits(compiles, { c = new C; }));

}