Is it safe/recommended to use wp_enqueue_script function outside the functions.php file?

I created multiple post formats, and when i use an audio post format, i want to include some additional javascript for the audio player.

So, i include the content-audio.php like this:

<?php while ( have_posts() ) : the_post(); ?>
    <?php get_template_part( 'blog/content', get_post_format() ); ?>
<?php endwhile; ?>

This loads the blog/content-audio.php as expected:

<article id="post-<?php the_ID(); ?>" <?php post_class(); ?>>
    <?php
    $att_args = array(
        'post_type'      => 'attachment',
        'numberposts'    => 1,
        'post_status'    => null,
        'post_parent'    => $post->ID,
        'post_mime_type' => 'audio',
        'orderby'        => 'menu_order'
    );
    $attachments = get_posts( $att_args );
    if( $attachments ): ?>
        <?php wp_enqueue_script('mediaelement-js'); ?>
        <?php foreach( $attachments as $attachment ): ?>
            <?php $attachmenturl=wp_get_attachment_url($attachment->ID); ?>
            <audio id="player2" src="https://wordpress.stackexchange.com/questions/83129/<?php echo $attachmenturl; ?>" type="audio/mp3" controls="controls"></audio>   
        <?php endforeach; ?>
    <?php endif; ?>
    <?php the_title(); ?>
</article>

Can i use the wp_enqueue_script() function inside this file? It’s working fine, but i’m curious if this is the right way to do it.

As of WordPress 3.4, calls to wp_enqueue_script() can be made inline. So, it is perfectly acceptable to call it where needed, such as inside a shortcode callback, or conditionally based upon returned queries, as you’ve done here.