Test if there are older posts in wordpress

I've got this function:

<?php next_posts_link( __( '<span class="meta-na开发者_如何学编程v">&larr;</span> Older posts') ); ?>

It creates a link if there are older posts. How do I do something on the condition that there are no older posts? Anything I do that uses this function only seems to echo the link.

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Simply add a get_ to the function :)

<?php 
if (get_next_posts_link()) {}
?>