diff --git a/csv_check.php b/csv_check.php
index ac767bf..273c728 100644
--- a/csv_check.php
+++ b/csv_check.php
@@ -81,20 +81,12 @@ if ($error != 0) echo '<br><b style="color:#990000;">Not allowed tags found !</b
 echo '<br><br>2: Not allowed multiple use of tags (column names)?';
 $compare = array_unique($zeile);
 
-function identical_values($arrayA, $arrayB) {
-    sort($arrayA);
-    sort($arrayB);
-    return $arrayA == $arrayB;
-
-}
-
 $result = identical_values($zeile, $compare);
 if ($result == false) {
     echo '<br><b style="color:#990000;">There are dublicate column names !</b>';
     $error = $error + 1;
 }
-else
-{
+else {
     echo '<br><i style="font-style:normal;color:#009900;">No dublicate column names !</i>';
 }
 
@@ -102,12 +94,10 @@ else
 //// Get values into memory for following checks
 $fp = fopen ( $csv_datei, 'r' );
 $y = 0;
-while ( $zeile = fgetcsv ( $fp, 100000, ';' ) )
-{
+while ($zeile = fgetcsv($fp, 100000, ';')) {
+
     $y++;
-    //echo '<br>';print_r($zeile);
-    for ($x = 0; $x < count ( $zeile ); $x++)
-    {
+    for ($x = 0; $x < count ( $zeile ); $x++) {
         $inhalt[$y][$x] = str_replace("'", "\'", $zeile[$x]);
     }
 }
@@ -118,25 +108,21 @@ echo '<br><br>3: Mandatory tags available and always filled in?';
 unset($inv_array);
 $inv_error = 0;
 
-function get_duplicates($array)
-{
+function get_duplicates($array) {
     return array_unique( array_diff_assoc( $array, array_unique( $array ) ) );
 
 }
 
 $mandatory = array('inventory_number','object_type','object_title','object_description');
-for ($i = 0; $i < count ($mandatory); $i++)
-{
+for ($i = 0; $i < count($mandatory); $i++) {
     if (!in_array($mandatory[$i], $erstezeile)) {
         echo '<br><i style="font-style:normal;color:#990000;">Mandatory: Column <b>' . $mandatory[$i] . '</b> missing</i>';
         $error = $error + 1;
         $inv_error = $inv_error + 1;
     }
-    else
-    {
+    else {
         $spaltenr = array_search($mandatory[$i], $erstezeile);
-        for ($j = 0; $j < $y; $j++)
-        {
+        for ($j = 0; $j < $y; $j++) {
             if ($inhalt[$j + 1][$spaltenr] == '') {
                 echo '<br><i style="font-style:normal;color:#990000;">Missing value for <b>' . $mandatory[$i] . '</b> in row ' . ($j + 1) . '</i>';
                 $error = $error + 1;
diff --git a/functions/functions.php b/functions/functions.php
index ef83a83..4f76f69 100644
--- a/functions/functions.php
+++ b/functions/functions.php
@@ -1,6 +1,10 @@
 <?PHP
 /**
  * Generic collection of functions used in CSVXML.
+ *
+ * @file
+ *
+ * @author
  */
 declare(strict_types = 1);
 
@@ -164,9 +168,9 @@ function generateHelpTooltip(string $identifier, string $title, string $explica,
  *
  * @param DOMDocument $xmlDoc XML object.
  *
- * @return void
+ * @return string
  */
-function printDOMDocToXML(DOMDocument $xmlDoc) {
+function printDOMDocToXML(DOMDocument $xmlDoc):string {
 
     return '<?xml version="1.0" encoding="UTF-8"?>' . $xmlDoc->saveXML($xmlDoc->documentElement);
 
@@ -187,9 +191,8 @@ function createTextDomElement(DOMDocument $xmlDoc, string $tag, string $content)
         $element = $xmlDoc->createElement($tag);
     }
     catch (DOMException $e) {
-            print_r($e);
-            print_r($tag);
-            exit;
+        echo "Error at " . __FILE__ . ", line #" . __LINE__;
+        exit;
     }
 
     $element->appendChild($xmlDoc->createTextNode($content));
@@ -213,7 +216,14 @@ function getBlankRecordChannel():array {
 
 }
 
-function rrmdir($dir) {
+/**
+ * Function for removing a directory with all its contents.
+ *
+ * @param string $dir File path of the directory to remove.
+ *
+ * @return void
+ */
+function rrmdir(string $dir) {
     if (is_dir($dir)) {
         $objects = scandir($dir);
         foreach ($objects as $object) {
@@ -226,3 +236,18 @@ function rrmdir($dir) {
     }
 
 }
+
+/**
+ * Function for checking if two arrays have identical values / contents.
+ *
+ * @param array $arrayA First array to compare.
+ * @param array $arrayB Second array to compare.
+ *
+ * @return boolean
+ */
+function identical_values(array $arrayA, array $arrayB):bool {
+    sort($arrayA);
+    sort($arrayB);
+    return $arrayA == $arrayB;
+
+}