isNullable

1 import std.typecons : Nullable;
2 
3 class C {}
4 
5 static assert( isNullable!(C));
6 static assert( isNullable!(int*));
7 static assert( isNullable!(int[]));
8 static assert( isNullable!(const(int)[]));
9 static assert(!isNullable!(int[3]));
10 static assert( isNullable!(string));
11 static assert( isNullable!(Nullable!int));
12 static assert(!isNullable!(int));
13 
14 struct S
15 {
16     int value;
17     static immutable nullValue = typeof(this).init;
18 }
19 
20 struct S2 { C x, y; }
21 static assert(!isNullable!S2);
22 
23 struct S3 { int x, y; }
24 static assert(!isNullable!S3);
25 
26 struct S4 { C x, y; alias nullifier = x; }
27 static assert(isNullable!S4);