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question.php

@@ -113,7 +113,7 @@ class qtype_stack_question extends question_graded_automatically_with_countback
     public $seed = null;
 
     /**
-     * @var array stack_cas_session STACK specific: session of variables.
+     * @var stack_cas_session2 STACK specific: session of variables.
      */
     protected $session;
 
@@ -1015,7 +1015,7 @@ class qtype_stack_question extends question_graded_automatically_with_countback
      * @param stack_cas_session $session the CAS session to add the question variables to.
      */
     public function add_question_vars_to_session(stack_cas_session2 $session) {
-        // Question vars will always get added to the begining of whatever session you give.
+        // Question vars will always get added to the beginning of whatever session you give.
         $this->session->prepend_to_session($session);
     }
 

stack/cas/cassession2.class.php

@@ -101,10 +101,20 @@ class stack_cas_session2 {
         $this->instantiated = false;
     }
 
+    /**
+     * Add all the statements from this session at the start of the target session.
+     *
+     * @param stack_cas_session2 $target
+     */
     public function prepend_to_session(stack_cas_session2 $target) {
         $target->statements = array_merge($this->statements, $target->statements);
     }
 
+    /**
+     * Add all the statements from this session at the end of the target session.
+     *
+     * @param stack_cas_session2 $target
+     */
     public function append_to_session(stack_cas_session2 $target) {
         $target->statements = array_merge($target->statements, $this->statements);
     }