functions.php

<?php // added for syntax highlighting.

add_shortcode( 'coauthors', 'coauthors_func' );
function coauthors_func( $atts ) {
	$atts = shortcode_atts( array(
		'between' => null,
		'betweenLast' => null,
		'before' => null,
		'after' => null,
	), $atts, 'coauthors' );

	return coauthors__echo('display_name', 'field', array(
		'between' => $atts['between'],
		'betweenLast' => $atts['betweenLast'],
		'before' => $atts['before'],
		'after' => $atts['after'],
	), null, false );
}

add_shortcode( 'coauthors_posts_links', 'coauthors_posts_links_func' );
function coauthors_posts_links_func( $atts ) {
	$atts = shortcode_atts( array(
		'between' => null,
		'betweenLast' => null,
		'before' => null,
		'after' => null,
	), $atts, 'coauthors' );

	return coauthors__echo('coauthors_posts_links_single', 'callback', array(
		'between' => $atts['between'],
		'betweenLast' => $atts['betweenLast'],
		'before' => $atts['before'],
		'after' => $atts['after'],
	), null, false );
}

add_shortcode( 'coauthors_links', 'coauthors_links_func' );
function coauthors_links_func( $atts ) {
	$atts = shortcode_atts( array(
		'between' => null,
		'betweenLast' => null,
		'before' => null,
		'after' => null,
	), $atts, 'coauthors' );

	return coauthors__echo('coauthors_links_single', 'callback', array(
		'between' => $atts['between'],
		'betweenLast' => $atts['betweenLast'],
		'before' => $atts['before'],
		'after' => $atts['after'],
	), null, false );
}