Implement Collection

src/collection/reduceOrNull.ts

@@ -0,0 +1,8 @@
+export function reduceOrNull<T>(value: T[], accumulate: (acc: T, it: T) => T): T | null {
+    if (value.length === 0) return null;
+    let acc = value[0];
+    for (let index = 1; index < value.length; index++) {
+        acc = accumulate(acc, value[index]);
+    }
+    return acc;
+}