Add Custom hybid type.

src/TG.php

@@ -84,6 +84,19 @@ public static function compound(TypeGenerator $t1, TypeGenerator $t2): Compound
         return Compound::new($t1, $t2);
     }
 
+    /**
+     * @template V
+     *
+     * @param TypeGenerator<V> $type
+     * @param Closure(TypeGenerator<V>): V $generator
+     *
+     * @return Custom<V>
+     */
+    public static function custom(TypeGenerator $type, Closure $generator): Custom
+    {
+        return Custom::new($type, $generator);
+    }
+
     public static function datetime(?DateTimeInterface $from = null, ?DateTimeInterface $to = null): DateTimeType
     {
         return DateTimeType::new($from, $to);

src/Types/Hybrid/Custom.php

@@ -0,0 +1,84 @@
+<?php
+
+/**
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace loophp\TypedGenerators\Types\Hybrid;
+
+use Closure;
+use Iterator;
+use loophp\TypedGenerators\Types\TypeGenerator;
+
+/**
+ * @template T
+ *
+ * @implements TypeGenerator<T>
+ */
+final class Custom implements TypeGenerator
+{
+    /**
+     * @var Closure(TypeGenerator<T>): T
+     */
+    private Closure $generator;
+
+    /**
+     * @var TypeGenerator<T>
+     */
+    private TypeGenerator $type;
+
+    /**
+     * @param TypeGenerator<T> $type
+     * @param Closure(TypeGenerator<T>): T $generator
+     */
+    public function __construct(TypeGenerator $type, Closure $generator)
+    {
+        $this->type = $type;
+        $this->generator = $generator;
+    }
+
+    /**
+     * @return T
+     */
+    public function __invoke()
+    {
+        return $this->identity(($this->generator)($this->type));
+    }
+
+    /**
+     * @return Iterator<int, T>
+     */
+    public function getIterator(): Iterator
+    {
+        // @phpstan-ignore-next-line
+        while (true) {
+            yield $this->__invoke();
+        }
+    }
+
+    /**
+     * @param T $input
+     *
+     * @return T
+     */
+    public function identity($input)
+    {
+        return $this->type->identity($input);
+    }
+
+    /**
+     * @template V
+     *
+     * @param TypeGenerator<V> $type
+     * @param Closure(TypeGenerator<V>): V $generator
+     *
+     * @return Custom<V>
+     */
+    public static function new(TypeGenerator $type, Closure $generator): self
+    {
+        return new self($type, $generator);
+    }
+}

tests/unit/TGTest.php

@@ -84,6 +84,15 @@ public function typeProvider()
             'class' => Compound::class,
         ];
 
+        yield [
+            'method' => 'custom',
+            'arguments' => [
+                new StringType(),
+                static fn (): string => 'hello',
+            ],
+            'class' => Custom::class,
+        ];
+
         yield [
             'method' => 'datetime',
             'arguments' => [],