functions.php

<?php

if( ! function_exists( 'array_insert' ) ) {
	/**
	 * Insert an array into another array before/after a certain key
	 *
	 * @param array  $array    The initial array
	 * @param array  $pairs    The array to insert
	 * @param string $key      The certain key
	 * @param string $position Wether to insert the array before or after the key
	 *
	 * @return array
	 */
	function array_insert( $array, $pairs, $key, $position = 'after' ) {

		$key_pos = array_search( $key, array_keys( $array ) );
		if( 'after' == $position )
			$key_pos ++;
		if( FALSE !== $key_pos ) {
			$result = array_slice( $array, 0, $key_pos );
			$result = array_merge( $result, $pairs );
			$result = array_merge( $result, array_slice( $array, $key_pos ) );
		} else {
			$result = array_merge( $array, $pairs );
		}

		return $result;
	}
}