Evaluate: support to show steps of parsing and evaluation.

Form: Error Message if multiple forms have the same name.

qfq/Evaluate.php

@@ -26,6 +26,7 @@ class Evaluate {
     private $endDelimiter = '';
     private $endDelimiterLength = 0;
     private $sqlKeywords = array('SELECT ', 'INSERT ', 'DELETE ', 'UPDATE ', 'SHOW ');
+    private $debugStack = array();
 
 
     public function __construct(Store $store, Database $db, $startDelimiter = '{{', $endDelimiter = '}}') {
@@ -43,7 +44,7 @@ class Evaluate {
      * @param $tokenArray
      * @return mixed
      */
-    public function parseArray($tokenArray) {
+    public function parseArray($tokenArray, $flagDebug = false) {
         $arr = array();
 
         foreach ($tokenArray as $key => $value) {
@@ -76,6 +77,8 @@ class Evaluate {
 
         while ($posFirstClose !== false) {
 
+            $this->debugStack[] = $line . " [$recursion]";
+
             $posMatchOpen = strrpos(substr($line, 0, $posFirstClose), $this->startDelimiter);
             if ($posMatchOpen === false) {
                 throw new \qfq\exceptions\UserException("Missing open delimiter: $line", ERROR_MISSING_OPEN_DELIMITER);
@@ -86,6 +89,7 @@ class Evaluate {
             $match = substr($line, $posMatchOpen + $this->startDelimiterLength, $posFirstClose - $posMatchOpen - $this->startDelimiterLength);
 
             $evaluated = $this->substitute($match);
+            $this->debugStack[] = $line . " [$recursion]";
 
             // If an array is returned, break everything and return this assoc array.
             if (is_array($evaluated)) {
@@ -150,4 +154,8 @@ class Evaluate {
         // nothing replaced: put ticks around, to sanatize strings for SQL statements. Nothing to substitute is not a wished situation.
         return ($value === false) ? "'" . $token . "'" : $value;
     }
+
+    public function getDebug() {
+        return '<pre>' . implode("\n", $this->debugStack) . '</pre>';
+    }
 }
\ No newline at end of file

qfq/Form.php

@@ -176,7 +176,7 @@ class Form {
         $formName = $this->getFormName();
         $this->store->setVar(SYSTEM_FORM, $formName, STORE_SYSTEM);
 
-        $this->formSpec = $this->eval->parseArray($this->db->sql("SELECT * FROM Form AS f WHERE f.name LIKE ? AND f.deleted='no'", ROW_EXACT_1, [$formName]));
+        $this->formSpec = $this->eval->parseArray($this->db->sql("SELECT * FROM Form AS f WHERE f.name LIKE ? AND f.deleted='no'", ROW_EXACT_1, [$formName], 'Form not found or multiple forms with the same name.'));
         HelperFormElement::explodeParameter($this->formSpec);
 
         // Clear