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

[Ingo Schwarze]

Hi Jeff,

Jeff Conrad wrote on Fri, Feb 08, 2019 at 04:25:51AM +0000:
> On Wednesday, February 6, 2019 6:39 AM, Ingo Schwarze wrote

>> BENEFITS:
>> ---------
>>  - stop relying on a historic meaning of ASCII 0c60
>>    that was never portable and that conflicts with Unicode

> I think "historic" is pretty context dependent.  As nearly as I can
> tell, ASA/ANSI X3.4 has called for 0x60 to encode "accent grave".

Absolutely not:

  http://worldpowersystems.com/ARCHIVE/codes/X3.4-1963/page5.JPG

In that standard, 0x60 was still unassigned, and in the next version,
the ambiguity is already stated.

I'm not aware that any version of ASCII ever resolved the ambiguity
that 0x60 can represent either "accent grave" or "opening single
quote".  However, in Unicode, U+0060 is unambiguously "accent grave".
In that sense, i do think calling usage of 0x60 for an opening
single quote "historic" is accurate.

>> DOWNSIDES:
>> ----------
>>  - looks worse with traditional fonts that provide an "opening quote"
>>    glyph for ASCII 0x60 rather than an "accent grave" glyph

> Again, I think "traditional" depends on which tradition one has
> followed.

That is of course true.  There are also traditional fonts treating
0x60 as "accent grave".  That's why i qualified "traditional fonts"
with "that provide", implying that modern (i.e. Unicode-compatible)
fonts always provide an "accent grave" at that code point.

Yours,
  Ingo