(page-url: ) → String
This macro produces the full URL of the story's HTML page, as it is in the player's browser.
(if: (page-url:) contains "#cellar") will be true if the URL contains the #cellar hash.
(if: (page-url:) contains "#cellar")
This may be changed in a future version of Harlowe to return a datamap containing more
descriptive values about the URL, instead of a single string.