Re: [groff] modernize -T ascii rendering of opening single quote

[Jeff Conrad]

On Friday, February 8, 2019 6:18 AM, Ingo Schwarze wrote

> you seem to be reading too much into various sources,

Quite likely, but perhaps no more so than anyone else.  My point was
simply that the distinction between “historical” and “modern” isn’t very
helpful.  If indeed X3.4-1967 called for accent grave at 0x60, the “modern”
era predated nroff. More on this below ...

This isn’t to say that there wasn’t ambiguity, as later versions
expressly permitted “national” variations; this is briefly discussed in
RFC2046:

    https://tools.ietf.org/html/rfc2046

> but fortunately, it only tangentially affects what matters to the
> proposed patch: there can be little doubt that fonts more commonly
> show 0x60 as a grave accent today, and likely also in the past, and
> that that practice better matches most (in particular international)
> standards.

Agree.  The history is largely tangential to the issue at hand.

> While the Fisher paper appears to be a respectable source, it is also
> not authoritative.

Depends, I guess, on what’s “authoritative.”  Perhaps all the sources
were faked (nowadays, one can never be sure).

> The mere shape of the glyph in the table is obviously not
> saying anything.

It seems to me that it would take a pretty bad muff to confuse an
opening quote and accent grave.

> > It's also consistent with ANSI X3.4-1986:
> >
> >     www.columbia.edu/kermit/ascii.html
> 
> Again, not authoritative, but an interpretation by a random person.

Here’s an “official” version:

    http://unicode.org/L2/L2006/06388-review-incits4.pdf

It does include caveats about 0x60.

> Jukka Korpela quotes a private communication from Eric Fisher
>   http://jkorpela.fi/latin1/ascii-hist.html#60
> indicating that showing 0x60 as a grave accent may have *always*
> been more common except possibly in the US.

I’m not sure it was common even in the US.

I discussed this with Doug Kerr, one of the authors (and the principal
editor) of X3.4-1967.  He assures me that accent grave was coded at
0x60; the intent was to provide the *option* to use 0x60 and 0x27 for
opening and closing quotes, but that this was in no way a recommendation
for actual practice.  He personally has used a neutral apostrophe for
opening and closing single quotes when in ASCIIville, just like many of
us. This, of course, is a personal preference rather than an
authoritative statement.

Doug has an interesting discussion on ASCII vs.  MS “ANSI,” which
touches on some of the issues we’ve been discussing:

    http://dougkerr.net/Pumpkin/articles/ASCII_ANSI.pdf

I think a good inference can be drawn from the behavior of “smart”
quotes: typically, neutral apostrophes are converted to opening or
closing single quotes at the beginnings or ends of words; nothing is
done with accent grave at the beginning of a word.  This suggests that
most people instinctively use a neutral apostrophe for opening and
closing single quotes, similar to what they do for double quotes.  This
suggests that the guiding principle is “match typewriter output,” even
though a lot of folks nowadays have no idea what a typewriter is.

Jeff