[WordPress] Using Functions in Place of Globals: get_post_field

00-get-post-slug.php

<?php
/**
 * Retrieves the slug for the current post via the current post's
 * post_name property.
 *
 * @return string the slug of the post.
 */
function getPostSlug(): string
{
  global $post;
  return $post->post_name;
}

01-get-post-slug-via-field.php

<?php

/**
 * Generates a boolean value based on the presence of a post slug.
 *
 * @return bool True if there is a slug; otherwise, false.
 */
function hasPostSlug(): bool
{
  return ('' === getPostSlug());
}

/**
 * Retrieves the slug for the current post via the get_post_field
 * API function.
 *
 * @return string the slug of the post.
 */
function getPostSlug(): string
{
  return get_post_field('post_name', get_the_ID());
}

03-get-post-slug-example.php

<?php

if (hasPostSlug()) {
  echo getPostSlug();
}