add ifPresent consumer for Option (#98)

Author: akondas

src/Control/Option.php

@@ -70,6 +70,16 @@ public function isPresent(): bool
         return !$this->isEmpty();
     }
 
+    /**
+     * @param callable(T): void $consumer
+     */
+    public function ifPresent(callable $consumer): void
+    {
+        if ($this->isPresent()) {
+            $consumer($this->get());
+        }
+    }
+
     /**
      * @template U
      *

tests/Control/OptionTest.php

@@ -182,4 +182,10 @@ public function testOptionIsPresent(): void
         self::assertTrue(Option::some(null)->isPresent());
         self::assertFalse(Option::none()->isPresent());
     }
+
+    public function testOptionIfPresent(): void
+    {
+        Option::none()->ifPresent(fn ($v) => throw new \RuntimeException('impossible is nothing'));
+        Option::of('a')->ifPresent(fn ($v) => self::assertSame('a', $v));
+    }
 }