public void MaybeSupportsMultiLevelChaining()
{
var items = GetTestItems();
var maybe1 = new Maybe <IEnumerable <TestGrandParentItem> >(items);
Func <IEnumerable <TestGrandParentItem>, TestGrandParentItem> chainFunc1 =
sequence => sequence.FirstOrDefault(i => i.Id == 1);
Func <TestGrandParentItem, TestParentItem> chainFunc2 =
i => i.Items.FirstOrDefault(p => p.Id == 11);
Func <TestParentItem, TestChildItem> chainFunc3 =
i => i.Items.FirstOrDefault();
var resultMaybe = maybe1
.Chain(chainFunc1)
.Chain(chainFunc2)
.Chain(chainFunc3);
Assert.IsTrue(resultMaybe.HasValue);
Assert.AreEqual(111, resultMaybe.Value.Id);
}
public void MaybeSupportsChaining()
{
var parent = new TestParentItem
{
Id = 111,
Items = new List <TestChildItem>
{
new TestChildItem {
Id = 1
},
new TestChildItem {
Id = 2
},
new TestChildItem {
Id = 3
},
new TestChildItem {
Id = 4
},
new TestChildItem {
Id = 5
},
new TestChildItem {
Id = 6
},
}
};
var maybe = new Maybe <TestParentItem>(parent);
Func <TestParentItem, Maybe <TestChildItem> > chainFunc = p =>
{
return(new Maybe <TestChildItem>(p.Items.FirstOrDefault(i => i.Id == 2)));
};
var resultMaybe = maybe.Chain(chainFunc);
Assert.IsTrue(resultMaybe.HasValue);
}
