Adding initial version of OVERRIDE(..) macro

macro.inc.php

@@ -171,3 +171,39 @@ function macro_UNWRAP($jsm, $content)
   $content = rtrim($content, '}');
   return $content;
 }
+
+function _array_merge_recursive_distinct(array $array1, array $array2)
+{
+  $merged = $array1;
+
+  foreach($array2 as $key => $value)
+  {
+    if(is_array($value) && isset($merged[$key]) && is_array($merged[$key]))
+      $merged[$key] = _array_merge_recursive_distinct($merged[$key], $value);
+    else
+      $merged[$key] = $value;
+  }
+
+  return $merged;
+}
+
+/**
+ * @global @raw_args
+ */
+function macro_OVERRIDE($jsm, $content)
+{
+  $items = \jzon_parse($content);
+  if(!is_array($items))
+    throw new Exception("OVERRIDE contents not an array");
+  if(sizeof($items) != 2)
+    throw new Exception("OVERRIDE array size is not 2, it's " . sizeof($items));
+
+  $merged = _array_merge_recursive_distinct($items[0], $items[1]);
+
+  $json = json_encode($merged, JSON_UNESCAPED_LINE_TERMINATORS | JSON_UNESCAPED_SLASHES);
+  $json = ltrim($json, '{');
+  $json = rtrim($json, '}');
+
+  return $json;
+}
+