/* Main */

{exp:channel:entries channel="pages"}
{title}
{page-body}
{embed="embed/getpromo" promo_title="{left_promo_code"}"}
{/exp:channel:entries}

/* Getpromo */

{if {embed:left_promo_code}}
{embed:left_promo_code}
{if:else}
<p>No promo code here! Nothing to see! Move along people!</p>
{/if}