refactor: Update Collapse operation in point free style. (#182)

loophp · Aug 18, 2021 · 02c61a1 · 02c61a1
1 parent 0fe81c7
commit 02c61a1
Showing 1 changed file with 11 additions and 16 deletions.
diff --git a/src/Operation/Collapse.php b/src/Operation/Collapse.php
@@ -28,24 +28,19 @@ final class Collapse extends AbstractOperation
      */
     public function __invoke(): Closure
     {
-        return
+        $filterCallback =
             /**
-             * @param Iterator<TKey, iterable<TKey, T>|T> $iterator
-             *
-             * @return Generator<TKey, T>
+             * @param T $value
              */
-            static function (Iterator $iterator): Generator {
-                /** @var Closure(Iterator<TKey, T|iterable<TKey, T>>): Generator<TKey, iterable<TKey, T>> $filter */
-                $filter = Filter::of()(
-                    /**
-                     * @param T $value
-                     */
-                    static fn ($value): bool => is_iterable($value)
-                );
+            static fn ($value): bool => is_iterable($value);
 
-                foreach ($filter($iterator) as $value) {
-                    yield from $value;
-                }
-            };
+        /** @var Closure(Iterator<TKey, (T|iterable<TKey, T>)>): Generator<TKey, T> $pipe */
+        $pipe = Pipe::of()(
+            Filter::of()($filterCallback),
+            Flatten::of()(1),
+        );
+
+        // Point free style.
+        return $pipe;
     }
 }