isURI -package:yesod-page-cursor

Test if string contains a valid URI (an absolute URI with optional fragment identifier).
Test if supplied labal is a URI resource node
Types that can represent URLs. For example, to parse links containing Text.URI.URI from the modern-uri package, simply define the orphan instance:
instance IsURI Modern.URI where
uriFromText = left displayException . mkURI
uriToText = render
Test if string contains a valid URI reference (an absolute or relative URI with optional fragment identifier).
Type class for types which can be safely cast to UriLauncher, for instance with toUriLauncher.