public static async Task LinqIoTest()
{
var init = 5;
var console = new List <string>();
var computation =
from x in MaybeT.Lift(new Io <int>(() => Task.FromResult(1)))
from y in MaybeT.Lift(Io.AsIo(() => Task.FromResult(2)))
from _ in MaybeT.HoistIo(Maybe.JustIf(init > 0, () => new Unit()))
from z in MaybeT.Lift(Io.AsIo(() => { console.Add("func run"); return(Task.FromResult(init)); }))
select x + y + z;
var value = await computation.Run.Run();
Assert.True(value.HasValue);
Assert.Equal(1 + 2 + init, value.Value());
Assert.Single(console);
init = 0;
console = new List <string>();
value = await computation.Run.Run();
Assert.False(value.HasValue);
Assert.Empty(console);
}