wp_cycle

wp_cycle.php

<?php

/**
 * Cycle/alternate unlimited values of a given array.
 * 
 * For instance, if you call this function five times with
 * `wp_cycle( 'three', 'two', 'one' )`, you will in return get: three two one
 * three two. This is useful for loops and allows you to do things like cycle
 * HTML classes.
 *
 * EXAMPLE
 * 
 *     foreach ( $posts as $post ) {
 *         echo '<div class="'.wp_cycle('odd','even').'">...</div>';
 *     }
 * 
 * This would alternate between `<div class="odd">...</div>` and
 * `<div class="even">...</div>`.
 * 
 * You can pass any data as args and as many as you want, e.g.
 * `wp_cycle( array( 'foo', 'bar' ), false, 5, 'silly' )`
 *
 * @param mixed Accepts unlimited args
 * @return mixed
 */
function wp_cycle() {
	static $wp_cycle_curr_index;

	$args = func_get_args();
	$fingerprint = substr( sha1( serialize( $args ) ), 0, 7 );
	if ( ! is_array( $wp_cycle_curr_index ) ) {
		$wp_cycle_curr_index = array();
	}
	if ( ! isset( $wp_cycle_curr_index[ $fingerprint ] ) || ! is_int( $wp_cycle_curr_index[ $fingerprint ] ) ) {
		$wp_cycle_curr_index[ $fingerprint ] = -1;
	}
	$wp_cycle_curr_index[ $fingerprint ] = ++$wp_cycle_curr_index[ $fingerprint ] % count( $args );

	return $args[ $wp_cycle_curr_index[ $fingerprint ] ];
}