meaning of posts_selection in add_action

can anybody help? ??

Sometimes you need to dig through the code a little:

From https://adambrown.info/p/wp_hooks/hook/posts_selection?version=3.1&file=wp-includes/query.php

// Announce current selection parameters.  For use by caching plugins.
do_action( 'posts_selection', $where . $groupby . $orderby . $limits . $join );

yeah, I’ve seen that one already. so that is executed every time a query is made? sorry as I didn’t understand it much. Thanks for the response btw..

Whenever do_action() is called, all the add_action()s get invoked.

Imagine that you want to do X when Y happens. The core team have in their function the line do_action('y_has_happened', $with_this_data);

You can write in your theme or plugin:

add_action('y_has_happened', 'my_function_when_y_happens');
function my_function_when_y_happens($happened_with_this_data){
  // Do X (with the data).
}

Hence them being ‘hooks’ they are points that allow theme/plugin writers to hook into that point.

that makes sense now. Thanks a lot!

Glad to help. Don’t forget to mark the topic resolved ??