Providing Pipe Function see #141

composer.json

@@ -84,6 +84,7 @@
             "src/Functional/PartialRight.php",
             "src/Functional/Partition.php",
             "src/Functional/Pick.php",
+            "src/Functional/Pipe.php",
             "src/Functional/Pluck.php",
             "src/Functional/Poll.php",
             "src/Functional/Product.php",

src/Functional/Functional.php

@@ -309,6 +309,11 @@ final class Functional
      */
     const pick = '\Functional\pick';
 
+    /**
+     * @see \Functional\pipe
+     */
+    const pipe = '\Functional\pipe';
+
     /**
      * @see \Functional\pluck
      */

src/Functional/Pipe.php

@@ -0,0 +1,45 @@
+<?php
+/**
+ * Copyright (C) 2019 by Jesus Franco Martinez <[email protected]>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+namespace Functional;
+
+/**
+ * Provides a callable that applies the functions passed as arguments from left
+ * to right, first function is able to admit several arguments at once
+ * @link https://github.com/lstrojny/functional-php/issues/141
+ * @param callable[] ...$functions functions to be composed
+ * @return callable
+ */
+function pipe(...$functions): callable
+{
+    return function () use ($functions) {
+        $fun_args = \func_get_args();
+        $entryFunction = \array_shift($functions);
+        return \array_reduce(
+            $functions,
+            function ($prev, $current_fun) {
+                return \call_user_func($current_fun, $prev);
+            },
+            \call_user_func_array($entryFunction, $fun_args)
+        );
+    };
+}

tests/Functional/PipeTest.php

@@ -0,0 +1,57 @@
+<?php
+/**
+ * Copyright (C) 2019 by Jesus Franco Martinez <[email protected]>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+namespace Functional\Tests;
+
+use function Functional\pipe;
+
+class PipeTest extends AbstractTestCase
+{
+    public function testPipeFunction()
+    {
+        $closure1 = $this->prophesize(CustomTestClosure::class);
+        $closure1->__invoke('o', 'n', 'e')->willReturn('one');
+        $closure2 = $this->prophesize(CustomTestClosure::class);
+        $closure2->__invoke('one')->willReturn('one, two');
+        $closure3 = $this->prophesize(CustomTestClosure::class);
+        $closure3->__invoke('one, two')->willReturn('one, two, three');
+
+        $result = pipe(
+            $closure1->reveal(),
+            $closure2->reveal(),
+            $closure3->reveal()
+        )('o', 'n', 'e');
+
+        $this->assertEquals('one, two, three', $result);
+
+        $closure1->checkProphecyMethodsPredictions();
+        $closure2->checkProphecyMethodsPredictions();
+        $closure3->checkProphecyMethodsPredictions();
+    }
+}
+
+class CustomTestClosure
+{
+    public function __invoke()
+    {
+    }
+}