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<?php

/*--------------------------------------------------------------
 # "Link" Post Functions
 --------------------------------------------------------------*/

/**
 * Add "Link" Post Format
 */
function add_post_formats() {
	add_theme_support( 'post-formats', array( 'link' ) );
}
add_action( 'after_setup_theme', 'add_post_formats' );

/**
 * Link Post Format: Permalink Filter URL Replacement
 */
function filter_the_permalink( $get_permalink ) {
	global $post;

	if ( 'link' == get_post_format( $post->ID ) ) {
		if ( preg_match( '#^<a.+href=[\'"]([^\'"]+).+</a>#', $post->post_content, $matches ) ) {
			$get_permalink = esc_url( $matches[1] );
		}
	}

	return $get_permalink;
}
add_filter( 'the_permalink', 'filter_the_permalink', 10, 1 );