[spec] IRIs, IDNs, and all that international jazz

[Sean Conner]

It was thus said that the Great Solderpunk once stated:
> Feedback welcome, especially if I've overlooked anything, which is
> certainly possible.  What I'd be most interested in hearing, at this
> point, is client authors letting me know whether the standard library
> in the language their client is implemented in can straightforwardly:
> 
> 1. Parse and relativise URLs with non-ASCII characters (so, yes, okay,
>    technically not URLs at all, you know what I mean) in paths and/or
>    domains?
> 2. Transform back and forth between URIs and IRIs?
> 3. Do DNS lookups of IDNs without them being punycoded first?  You can
>    test this with räksmörgås.josefsson.org.

  For C, I'm sure there is code, somewhere, that can parse IRIs, but it's a
matter of finding them.  

  For Lua, the answers are:

	1. Yes.  I had to write some code [1][2], and modify some existing
	   code [3], but Lua now has modules to parse IRI and URIs.

	2. I can do IRI->URL, but not the other way---I have no need of a
	   URL->IRI as of yet.

	3. For my setups (systems I've been able to test), I cannot lookup
	   IDNs as is---I *have* to convert to punycode first.

  -spc

[1]	https://github.com/spc476/LPeg-Parsers/blob/master/iri.lua

[2]	https://github.com/spc476/lua-conmanorg/blob/master/src/idn.c

[3]	https://github.com/spc476/GLV-1.12556/blob/master/Lua/GLV-1/url-util.lua