This is my new answer to, “What’s your favorite relatively unknown part of Core?” (Previously, it was the declaration of human rights embedded into has_cap().)

It turns out there’s a much better way to fetch post meta than get_post_meta( $post->ID, 'foo', true ):

$post->foo

It’s really that simple. Behind the scenes, the reference to $post->foo is handled by WP_Post‘s magic getter, which in turn calls get_post_meta( $post->ID, 'foo', true ), making your code so much cleaner and more readable.

This was introduced 4 years ago in WordPress 3.5, but I just now stumbled upon it. Why has nobody ever told me this?

You can even extend it to introduce dynamically-generated fields, so you can call echo esc_html( $post->bar ) instead of $bar = some_custom_logic( get_post_meta( $post->ID, 'bar', true ) ); echo esc_html( $bar ).

add_filter( 'get_post_metadata', 'add_dynamic_post_meta', 10, 4 );

/**
 * Add dynamically-generated "post meta" to `\WP_Post` objects
 *
 * This makes it possible to access dynamic data related to a post object by simply referencing `$post->foo`.
 * That keeps the calling code much cleaner than if it were to have to do something like
 * `$foo = some_custom_logic( get_post_meta( $post->ID, 'bar', true ) ); echo esc_html( $foo )`.
 *
 * @param mixed  $value
 * @param int    $post_id
 * @param string $meta_key
 * @param int    $single   @todo handle the case where this is false
 *
 * @return mixed
 *      `null` to instruct `get_metadata()` to pull the value from the database
 *      Any non-null value will be returned as if it were pulled from the database
 */
function add_dynamic_post_meta( $value, $post_id, $meta_key, $single ) {
	$post = get_post( $post_id );

	if ( 'page' != $post->post_type ) {
		return $value;
	}

	switch ( $meta_key ) {
		case 'verbose_page_template':
			$value = "The page template is " . ( $post->_wp_page_template ?: 'not assigned' );
			break;
	}

	return $value;
}