https://github.com/mage2pro/core/issues/403

app/code/local/Df/Core/lib/array/map.php

@@ -141,10 +141,25 @@ function df_map_k($a1, $a2):array {return df_map($a1, $a2, [], [], DF_BEFORE);}
 function df_map_kr($a1, $a2):array {return df_map($a1, $a2, [], [], DF_BEFORE, true);}
 
 /**
- * 2016-11-08
- * Функция принимает аргументы в любом порядке.
- * @param callable|array(int|string => mixed)|array[]\Traversable $a1
- * @param callable|array(int|string => mixed)|array[]|\Traversable $a2
+ * 2016-11-08 Функция принимает аргументы в любом порядке.
+ * 2024-06-03
+ * 1.1) "Use the `iterable` type": https://github.com/mage2pro/core/issues/403
+ * 1.2) `iterable` is supported by PHP ≥ 7.1: https://3v4l.org/qNX1j
+ * 1.3) https://php.net/manual/en/language.types.iterable.php
+ * 2) We still can not use «Union Types» (e.g. `callable|iterable`) because they require PHP ≥ 8 (we need to support PHP ≥ 7.1):
+ * 2.1) https://php.watch/versions/8.0/union-types
+ * 2.2) https://3v4l.org/AOWmO
+ * @used-by df_category_children_map()
+ * @used-by df_modules_my()
+ * @used-by df_parse_colon()
+ * @used-by dfe_packages()
+ * @used-by dfe_portal_stripe_customers()
+ * @used-by \Df\Config\Source\Block::map()
+ * @used-by \Df\Directory\Model\ResourceModel\Country\Collection::mapFrom3To2()
+ * @used-by \Df\Directory\Model\ResourceModel\Country\Collection::mapFromCodeToName()
+ * @used-by \Df\Framework\Form\Element\Multiselect::getElementHtml()
+ * @param callable|iterable $a1
+ * @param callable|iterable $a2
  * @return array(int|string => mixed)
  */
-function df_map_r($a1, $a2) {return df_map($a1, $a2, [], [], 0, true);}
+function df_map_r($a1, $a2):array {return df_map($a1, $a2, [], [], 0, true);}