From 0bfd8954a9e6e4e893fdab89f38f7cb258dbc588 Mon Sep 17 00:00:00 2001
From: widmogrod <widmogrod@gmail.com>
Date: Mon, 24 Oct 2016 00:45:04 +0200
Subject: [PATCH] Slowly introduce listt instead of native php array

---
 src/Functional/functions.php   | 16 +++++++++-------
 test/Functional/FoldrTest.php  | 23 +++++++++++++++++++++++
 test/Functional/ReduceTest.php | 23 +++++++++++++++++++++++
 3 files changed, 55 insertions(+), 7 deletions(-)
 create mode 100644 test/Functional/FoldrTest.php
 create mode 100644 test/Functional/ReduceTest.php

diff --git a/src/Functional/functions.php b/src/Functional/functions.php
index c7571e9..25eea0a 100644
--- a/src/Functional/functions.php
+++ b/src/Functional/functions.php
@@ -8,8 +8,8 @@ use Widmogrod\FantasyLand\Foldable;
 use Widmogrod\FantasyLand\Functor;
 use Widmogrod\FantasyLand\Monad;
 use Widmogrod\FantasyLand\Traversable;
-use Widmogrod\Primitive\Listt;
 use Widmogrod\Monad\Identity;
+use Widmogrod\Primitive\Listt;
 
 /**
  * @var callable
@@ -465,7 +465,9 @@ function foldr(callable $callable, $accumulator = null, Foldable $foldable = nul
         return reduce(
             $callable,
             $accumulator,
-            toFoldable(reduce(flip(append), [], $foldable))
+            reduce(function ($accumulator, $value) {
+                return concatM(Listt::of([$value]), $accumulator);
+            }, Listt::of([]), $foldable)
         );
     }), func_get_args());
 }
@@ -821,8 +823,8 @@ const traverse = 'Widmogrod\Functional\traverse';
  *
  * Map each element of a structure to an action, evaluate these actions from left to right, and collect the results
  *
- * @param callable $transformation  (a -> f b)
- * @param Traversable      $t t a
+ * @param callable $transformation (a -> f b)
+ * @param Traversable $t           t a
  *
  * @return Applicative     f (t b)
  */
@@ -856,7 +858,7 @@ function sequence($monads)
 /**
  * filterM :: Monad m => (a -> m Bool) -> [a] -> m [a]
  *
- * @param callable $f (a -> m Bool)
+ * @param callable $f                   (a -> m Bool)
  * @param array|Traversable $collection [a]
  *
  * @return Monad m [a]
@@ -896,8 +898,8 @@ function filterM(callable $f, $collection)
 /**
  * foldM :: Monad m => (a -> b -> m a) -> a -> [b] -> m a
  *
- * @param callable $f (a -> b -> m a)
- * @param mixed $initial a
+ * @param callable $f                    (a -> b -> m a)
+ * @param mixed $initial                 a
  * @param array|\Traversable $collection [b]
  *
  * @return mixed m a
diff --git a/test/Functional/FoldrTest.php b/test/Functional/FoldrTest.php
new file mode 100644
index 0000000..a4cac53
--- /dev/null
+++ b/test/Functional/FoldrTest.php
@@ -0,0 +1,23 @@
+<?php
+
+namespace test\Functional;
+
+use Widmogrod\Functional as f;
+use Widmogrod\Primitive\Listt;
+
+class FoldrTest extends \PHPUnit_Framework_TestCase
+{
+    public function test_foldr()
+    {
+        $list = Listt::of([1, 2, 3, 4]);
+
+        $result = f\foldr(function ($accumulator, $value) {
+            return f\concatM($accumulator, Listt::of([$value + 1]));
+        }, Listt::of([]), $list);
+
+        $this->assertEquals(
+            $result,
+            Listt::of([5, 4, 3, 2])
+        );
+    }
+}
diff --git a/test/Functional/ReduceTest.php b/test/Functional/ReduceTest.php
new file mode 100644
index 0000000..de4aaeb
--- /dev/null
+++ b/test/Functional/ReduceTest.php
@@ -0,0 +1,23 @@
+<?php
+
+namespace test\Functional;
+
+use Widmogrod\Functional as f;
+use Widmogrod\Primitive\Listt;
+
+class ReduceTest extends \PHPUnit_Framework_TestCase
+{
+    public function test_reduce()
+    {
+        $list = Listt::of([1, 2, 3, 4]);
+
+        $result = f\reduce(function ($accumulator, $value) {
+            return f\concatM($accumulator, Listt::of([$value + 1]));
+        }, Listt::of([]), $list);
+
+        $this->assertEquals(
+            $result,
+            Listt::of([2, 3, 4, 5])
+        );
+    }
+}
-- 
2.11.0