How to set Drupal module hooks weight OR call your module hook in last posit

7 system.api.php hook_module_implements_alter(&$implementations, $hook)
8 module.api.php hook_module_implements_alter(&$implementations, $hook)

Alter the registry of modules implementing a hook.

This hook is invoked during module_implements(). A module may implement this hook in order to reorder the implementing modules, which are otherwise ordered by the module’s system weight.

Note that hooks invoked using drupal_alter() can have multiple variations (such as hook_form_alter() and hook_form_FORM_ID_alter() ). drupal_alter() will call all such variants defined by a single module in turn. For the purposes of hook_module_implements_alter(), these variants are treated as a single hook. Thus, to ensure that your implementation of hook_form_FORM_ID_alter() is called at the right time, you will have to change the order of hook_form_alter() implementation in hook_module_implements_alter().

Parameters

$implementations: An array keyed by the module’s name. The value of each item corresponds to             a $group, which is usually FALSE, unless the implementation is in a file named $module.$group.inc.

$hook: The name of the module hook being implemented.

Code

[code type=php]

function hook_module_implements_alter(&$implementations, $hook) {
if ($hook == ‘rdf_mapping’) {
// Move my_module_rdf_mapping() to the end of the list. module_implements()
// iterates through $implementations with a foreach loop which PHP iterates
// in the order that the items were added, so to move an item to the end of
// the array, we remove it and then add it.
$group = $implementations[‘my_module’];
unset($implementations[‘my_module’]);
$implementations[‘my_module’] = $group;
}
}

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