How to parse a guid from a uri to using in a redirection

And actually, I lied. The unencoded hash is NOT legal in the submitted URI path. See RFC 3986 section 3.5:

Fragment identifiers have a special role in information retrieval
systems as the primary form of client-side indirect referencing,
allowing an author to specifically identify aspects of an existing
resource that are only indirectly provided by the resource owner.  As
such, the fragment identifier is not used in the scheme-specific
processing of a URI; instead, the fragment identifier is separated
from the rest of the URI prior to a dereference, and thus the
identifying information within the fragment itself is dereferenced
solely by the user agent, regardless of the URI scheme.

In other words, the user-agent is supposed to strip everything from the URI path starting with the hash, and use it for object internal dereferencing (as happens, for example, in an HTML document with the use of