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filter is not described

pre_user_id filter-hook . WP 1.5.0

Filters the comment author's user id before it is set.

The first time this filter is evaluated, 'user_ID' is checked (for back-compat), followed by the standard 'user_id' value.

Usage

add_filter( 'pre_user_id', 'filter_function_name_5251' );
function filter_function_name_5251( $user_ID ){
	// filter...

	return $user_ID;
}
$user_ID(int)
The comment author's user ID.

Changelog

Since 1.5.0 Introduced.

Where the hook is called

wp_filter_comment()
pre_user_id
wp-includes/comment.php 1943
$commentdata['user_id'] = apply_filters( 'pre_user_id', $commentdata['user_ID'] );
wp-includes/comment.php 1946
$commentdata['user_id'] = apply_filters( 'pre_user_id', $commentdata['user_id'] );

Where the hook is used (in WP core)

Usage not found!