When creating a new WP_Query, running the_post() on the new object resets global $post

[bsdeluxe]

This happens when running multiple loops in a page. If a new WP_Query object is created, $post should only be changed within the scope of that object, right?

To replicate:

// in a template called from a page

echo $post->ID; // the ID of the page
$new_obj = new WP_Query();
$new_obj->query("some valid querystring");
if ($new_obj->have_posts()) : while ($new_obj->have_posts()) : $new_obj->the_post();
 // .. do your loop stuff
endwhile; endif;
echo $post->ID; // not the same as the first one

Suggested patch attached.

[bsdeluxe]

Patch to fix scope issue on the_post

[nacin]

$post is a global central to a lot of WP functionality. What you're trying to do can be done via numerous multiple loop solutions. See ​http://codex.wordpress.org/The_Loop#Multiple_Loops.

[scribu]

What nacin said and also, with your patch, how would the global $post be populated in the main query?

Suggest closing as 'worksforme'.

[filosofo]

I like the general idea of trying to move the WP_Query away from being overly dependent on globals. Unfortunately there are huge backwards-compatibility issues. Practically everybody assumes $post will be defined in the scope of a template file. Lots of themes and theme examples use $post->ID to get the current post's ID within the Loop.

Someday maybe.

[dd32]

call wp_reset_query() after your custom loop to reset it back to the main loop.

[scribu]

Replying to dd32:

call wp_reset_query() after your custom loop to reset it back to the main loop.

There you go.

Reopen when we drop PHP 4 for good.