[SPEC-CHANGE] Mandatory scheme in request and link URLs

[Waweic]

Hi, if I am not mistaken there are some errors in your list of valid
URI References.

> => gemini://example.net/path/foo.gemini Absolute URL - fully
> specified
> => //example.net/path/foo.gemini        relative URL - no scheme
> => /path/foo.gemini                     relative URL - no host
> => foo.gemini                           relative URL - no path
> => ../path/foo.gemini                   relative URL - relative

First of, these are not URLs, RFC 3986 specifies URIs and URI
References. As we are speaking about links, we need to speak about URI
References rather then URLs or URIs. Note that this does not apply to
requests, there we speak about URIs.

So instead, this would be the terminology I would use:

=> gemini://example.net/path/foo.gemini URI Reference
=> //example.net/path/foo.gemini        relative URI reference - no
scheme, absolute path
=> /path/foo.gemini                     relative URI Reference - no
host, absolute path
=> foo.gemini                           relative URI Reference - no
host, relative path (Note that this is not a reference without a
specified path, for that, it would have to begin with //.)
=> ../path/foo.gemini                   relative URI Reference - no
host, relative path

The following examples would also be valid:

=> gemini://example.net			URI Reference - empty path
=> //example.net			relative URI Reference - no
scheme, empty path
=> /					relative URI Reference - no
host, absolute path

Looking at the ABNF in Appendix A of RFC 3986, this gets pretty clear.
IMO the current solution is pretty good, requiring a URI for requests
and a URI Reference for links, this is as it should be.

If I read the spec change email correctly, now text/gemini documents
also require full URIs in the links, I don't think of this as a good
idea