#67 Add orEmpty, isEmpty implements

meian · Jan 29, 2022 · 75d9070 · 75d9070
1 parent 456acc5
commit 75d9070
Showing 1 changed file with 15 additions and 0 deletions.
diff --git a/empty.go b/empty.go
@@ -11,6 +11,21 @@ func empty[T any]() Iterable[T] {
 	return emptyIterable[T]{}
 }
 
+func orEmpty[T any](itb Iterable[T]) Iterable[T] {
+	if itb == nil {
+		return empty[T]()
+	}
+	return itb
+}
+
+func isEmpty[T any](itb Iterable[T]) bool {
+	if itb == nil {
+		return true
+	}
+	_, ok := itb.(emptyIterable[T])
+	return ok
+}
+
 func (itb emptyIterable[T]) Iterator() Iterator[T] {
 	return emptyIter[T]()
 }