wordpress : custom filter

custom-filter

<?php


function boj_posts_by_comments() {
	/* Default arguments. */
	$args = array(
		'post_type' = > 'post',
		'posts_per_page' = > 10,
		'order' = > 'DESC',
		'orderby' = > 'comment_count'
	);
	/* Apply filters to the arguments. */
	$args = apply_filters( 'boj_posts_by_comments_args', $args );
	/* Set up the output variable. */
	$out = '';
	/* Query posts from the database by the given arguments. */
	$loop = new WP_Query( $args );
	/* Check if posts are found. */
	if ( $loop-> have_posts() ) {
		/* Open the unordered list. */
		$out .= ' < ul class="posts-by-comments" > ';
		/* Loop through the posts. */
		while ( $loop-> have_posts() ) {
			$loop-> the_post();
			/* Add the post title to the list. */
			$out .= the_title( ' < li > ', ' < /li > ', false );
		}
		/* Close the unordered list. */
		$out .= ' < /ul > ';
	}
	/* Apply filters to the final output. */
	$out = apply_filters( 'boj_posts_by_comments', $out );
	/* Display the HTML. */
	echo $out;
}

//*************************
add_filter( 'boj_posts_by_comments_args', 'boj_change_posts_by_comments_args' );
function boj_change_posts_by_comments_args( $args ) {
	/* Change the value of the posts_per_page array key. */
	$args['posts_per_page'] = 15;
	/* Return the $args parameter. */
	return $args;
}

//**************************
add_filter( 'boj_posts_by_comments', 'boj_change_posts_by_comments' );
function boj_change_posts_by_comments( $out ) {
	/* Change the opening < ul > to an < ol > . */
	$out = str_replace( ' < ul ', ' < ol ', $out );
	/* Change the closing < /ul > to an < /ol > . */
	$out = str_replace( ' < /ul > ', ' < /ol > ', $out );
	/* Return the filtered HTML. */
	return $out;
}