From 63726893cb955dd7f121ca7d7890310360ad49d2 Mon Sep 17 00:00:00 2001
From: Jan Schneider <jan@horde.org>
Date: Wed, 22 Sep 2010 17:01:39 +0200
Subject: [PATCH] Add warnings. Throwing exceptions is expensive!!!

---
 framework/Core/lib/Horde.php | 6 +++++-
 horde/docs/CODING_STANDARDS  | 4 ++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/framework/Core/lib/Horde.php b/framework/Core/lib/Horde.php
index 901991d14..d60053730 100644
--- a/framework/Core/lib/Horde.php
+++ b/framework/Core/lib/Horde.php
@@ -1667,6 +1667,9 @@ HTML;
      * Call a Horde hook, handling all of the necessary lookups and parsing
      * of the hook code.
      *
+     * WARNING: Throwing exceptions is expensive, so use callHook() with care
+     * and cache the results if you going to use the results more than once.
+     *
      * @param string $hook  The function to call.
      * @param array  $args  An array of any arguments to pass to the hook
      *                      function.
@@ -1681,7 +1684,8 @@ HTML;
         $error = false;
         $hook_class = $app . '_Hooks';
 
-        if (empty(self::$_hooksLoaded[$app]) && !class_exists($hook_class, false)) {
+        if (empty(self::$_hooksLoaded[$app]) &&
+            !class_exists($hook_class, false)) {
             try {
                 self::loadConfiguration('hooks.php', null, $app);
             } catch (Horde_Exception $e) {}
diff --git a/horde/docs/CODING_STANDARDS b/horde/docs/CODING_STANDARDS
index 40733e17a..80126ddda 100644
--- a/horde/docs/CODING_STANDARDS
+++ b/horde/docs/CODING_STANDARDS
@@ -617,6 +617,10 @@ to a Horde_Exception before throwing.
 When throwing a Horde_Exception the error message provided should not be
 localized.
 
+Throwing exceptions is expensive, so use them carefully for logic flow. You
+should cache results of Horde::callHook() calls for example, if you expect them
+to not exist.
+
 
 Existence checking
 ==================
-- 
2.11.0