Merge pull request #74 from quexpl/master

PHP: Recursive with for loop

Author: nickjj

php/for_recursive.php

@@ -0,0 +1,50 @@
+<?php
+  $sections = [
+    [
+        "title" => "Getting started",
+        "reset_lesson_position" => false,
+        "lessons" => [
+            ["name" => "Welcome"],
+            ["name" => "Installation"],
+        ],
+    ],
+    [
+        "title" => "Basic operator",
+        "reset_lesson_position" => false,
+        "lessons" => [
+            ["name" => "Addition / Subtraction"],
+            ["name" => "Multiplication / Division"],
+        ],
+    ],
+    [
+        "title" => "Advanced topics",
+        "reset_lesson_position" => true,
+        "lessons" => [
+            ["name" => "Mutability"],
+            ["name" => "Immutability"],
+        ],
+    ],
+  ];
+
+  function append_position($item, $counter) {
+    $item['position'] = $counter++;
+    return [$item, $counter];
+  }
+
+  function process_items($items, $depth, $counter) {
+    for($i = 0; $i<count($items); $i++) {
+      [$item, $counter[$depth]] = append_position(array_shift($items), $counter[$depth]);
+
+      if (!empty($item['lessons'])) {
+        if ($item["reset_lesson_position"]) $counter[$depth+1] = 1;
+        [$item['lessons'],, $counter] = process_items($item['lessons'], $depth+1, $counter);
+      }
+
+      array_push($items, $item);
+    }
+
+    return [$items, $depth, $counter];
+  }
+
+  [$newSection] = process_items($sections, 0, [1, 1]);
+  print_r($newSection);