Re: [Editorial Errata Reported] RFC4013 (1812)

[Simon Josefsson <simon@xxxxxxxxxxxxx>]

RFC Errata System <rfc-editor@xxxxxxxxxxxxxx> writes:

> Section: 2.3
>
> Original Text
> -------------
> Section title is "Prohibited Output"
>
> Corrected Text
> --------------
> Section title should be "Prohibited Input"
>
> Notes
> -----
> Section 2.3 is talking about prohibited input, not prohibited output.

I'm not sure about this -- compare RFC 3454 section 5, the terminology
and design is about prohibiting code points in the _output_.

Testing for code points in the _output_ may be semantically different
from testing in the _input_.  Some other IDNA operation may modify code
points into one of the prohibited _output_ code points.  See RFC 3454
section 2, the map&normalize steps are taken before the prohibit step.

/Simon