On Sunday, 29 March 2015 at 23:19:31 UTC, Freddy wrote:
Is there any way to do a final switch statement in
std.variant's Algebraic.
Not currently. However, std.variant.visit is probably what you
want. It enforces that you handle all types contained in the
Algebraic.
import std.variant;
import std.stdio;
//For convenience as typeof(null) has no name
alias Null = typeof(null);
alias Maybe(T) = Algebraic!(T, Null);
void main()
{
Maybe!int n = 0;
writeln(n); //Prints 0
n = null;
writeln(n); //Prints null
//Prints I'm Null!
n.visit!(
(int i) = writeln(I'm an int!),
(Null n) = writeln(I'm Null!),
);
auto m = n.visit!(
(int i) = i,
(Null n) = -1,
);
writeln(m); //Prints -1
}