Some hooks have a parameter by reference.
Please refer to the source code to find out more about the context of the hook.
+--------------------------------+------+-----------------------------------------------+
| File | Line | Hook call |
+--------------------------------+------+-----------------------------------------------+
| index.php | 31 | Hook::apply('init') |
| index.php | 70 | Hook::apply('config.loaded', $config) |
| index.php | 92 | Hook::apply('before.action', $page) |
| index.php | 110 | Hook::apply('template.compile', $html) |
| index.php | 131 | Hook::apply('template.compiled', $html) |
| index.php | 140 | Hook::apply('template.compressed', $html) |
| index.php | 147 | Hook::apply('before.render') |
| index.php | 152 | Hook::apply('after.render') |
| app/Snipe.php | 98 | Hook::apply('snipe.loaded', $this) |
| app/Snipe.php | 121 | Hook::apply('snipe.loaded', $this) |
| design/default/index.phtml | 36 | Hook::apply('head.style') |
| design/default/index.phtml | 43 | Hook::apply('before.content') |
| design/default/index.phtml | 62 | Hook::apply('after.content') |
| design/default/index.phtml | 68 | Hook::apply('body.script') |
+--------------------------------+------+-----------------------------------------------+