initial checkin

Signed-off-by: Dr. Carsten Leue <carsten.leue@de.ibm.com>

predicate/bool.go

@@ -0,0 +1,25 @@
+package predicate
+
+func Not[A any](predicate func(A) bool) func(A) bool {
+	return func(a A) bool {
+		return !predicate((a))
+	}
+}
+
+// And creates a predicate that combines other predicates via &&
+func And[A any](second func(A) bool) func(func(A) bool) func(A) bool {
+	return func(first func(A) bool) func(A) bool {
+		return func(a A) bool {
+			return first(a) && second(a)
+		}
+	}
+}
+
+// Or creates a predicate that combines other predicates via ||
+func Or[A any](second func(A) bool) func(func(A) bool) func(A) bool {
+	return func(first func(A) bool) func(A) bool {
+		return func(a A) bool {
+			return first(a) || second(a)
+		}
+	}
+}