Why is ASCII DEL 0x7F excluded?

[SirWumpus]

In Forth 200x Draft 19.1 why is ASCII DEL 0x7F excluded from section 3.1.2.2 Control Characters? DEL is part of ASCII and treated as a control character, typically ^? on Unix-ish systems.

[ruv]

I don't think 0x7F is excluded. It is just not mentioned explicitly, but it's implicitly included in "all non-graphic characters":

All non-graphic characters included in the implementation-defined character set are defined in this standard as control characters. In particular, the characters {0 . . . 31}, which could be included in the implementation-defined character set, are control characters.

(emphasis added by me)

The characters sub-set {0 . . . 31} is mentioned as an example.

[SirWumpus]

This draft never fails to amaze in what it won't commit to. 3.1.2.2 is the first time implementation-defined character set is mentioned (out of 6 references in the document), yet its not discussed before that nor any rationale. They state ASCII is used, of which 0..31 are well defined controls including DEL, so how / when / why would you have an implementation-defined character set - maybe some rationale for 3.1.2, 3.1.2.1, 3.1.2.2 might help, for example:

   An `implementation-defined character set` can be any character set where 7-bit ASCII is a proper subset.
   For example UTF-8 encoding, Extended ASCII, Latin1 to name a few.

[ruv]

You could submit a proposal of such an improvement.

I would only say "shall be a superset of" instead of "can be" (see Chapter 2). And it should be appended into 3.1.2 (not 3.1.2.2).