Valdis Kletnieks writes:
-- citing RFC1345 only proves that Keld's interpretation
of ANSI X3.4 is that codepoint 41 octal is an exclamation point.
To be pragmatic, it is the interpretation of almost all people.
Ahh.. but that's the *current* interpretation. I've used a lot
of keyboards that were convinced that a 41 octal was a vertical
bar. I've used a lot of keyboards that didn't understand the
circumflex character (reading the Berkeley 'curses' source, you'll
come across the phrase "Hazeltine Brain Damage"...).
I have used ANSIs official registration of ASCII, in the ECME
registry according to ISO 2375, registration number 6, dated 1975/12/01.
It says on page 3.10:
2/1 ! Exclamation mark
5/14 ^ Upward arrow head circumflex accent
No "vertical bar", no "not sign" there.
Anyway I would not exclude that the official ANSI standard at one time
had provisions for the "not" and "vartical bar". But I would believe
that the current ASCII standard is in conformance with ISO 646,
which would exclude vague wording on the positions used for
! and ^ (well, at least for ! , ^ is at a national use position.)
Pragmatic decision: To make the PL/I subset fit into the requisite
number of characters, 2 ASCII codepoints are ambigiously defined,
so 2 similar-looking glyphs can share a codepoint.
At the time, "almost all people" interpreted these two characters
as "similar enough" to let it happen. Years later, people realize
that they are different characters and fix the problem.
There are similar examples on 7-bit use in scandinavia, where
{|}[\] are both used for the ASCII characters (eg in C programming)
and as national letters. RFC1345 has som mechanisms to specify this.
This is ugly, but quite useful.
Keld