sprintf

<?php     if ($len < $howMany) {

        return reject(

            new Exception\LengthException(

                \sprintf(

                    'Input array must contain at least %d item%s but contains only %s item%s.',

                    $howMany,

                    1 === $howMany ? '' : 's',

                    $len,

                    1 === $len ? '' : 's'

                )

            )

        );

    }