Re: [groff] hyphenation issues

[Dave Kemper]

Hi Werner,

I know groff isn't your primary focus anymore, so I'm pleased to see
you've tackled these hyphenation bugs and enhancements.


On 3/1/18, Werner LEMBERG <address@hidden> wrote:
> o The `.hy' request should now work as documented (again).
>   Additionally, I've added values 16 and 32 to hyphenate before the
>   last and after the first character, respectively.  There exist
>   languages (most notably Greek) that indeed allow (and use) such
>   hyphenation points.

In past groff releases, the user could have given .hy a (then
undefined) value of 16 or 32.  This would not have generated any error
or warning, and would have produced acceptable output.

Any older document that uses such a (previously undefined) .hy value
will now generate rather ugly output in some languages, such as
English.

>From a standpoint of backwards compatibility, is this a concern?  Yes,
such values were technically undefined before, but past groffs never
complained about them.  Yes, it's an edge case and probably rare to
nonexistent.  But the new results are so ugly, perhaps the user ought
to be warned.

Going forward, should groff generate a warning if a document contains
an undefined value of .hy, so that this problem will not recur with
any future changes?