Thank you Hans, this was very helpful. I found that the following
worked (apart from in two or three cases):

\startluacode
     fonts.handlers.otf.addfeature {
         name     = "iebpkerns",
         type     = "kern",
         data     = {
             [")"] = {
                 [","] = -80,
                 ["."] = -80,
                 [":"] = -80,
                 [";"] = -80,
                 [")"] = -80,
                 ["]"] = -80,
             },
             ["]"] = {
                 [","] = -80,
                 ["."] = -80,
                 [":"] = -80,
                 [";"] = -80,
                 [")"] = -80,
                 ["]"] = -80,
             },
         },
     }
\stopluacode



Best, Richard



-- 
Richard Mahoney | Indica et Buddhica

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-----Original Message-----
From: Hans Hagen <j.hagen@xs4all.nl>
To: mailing list for ConTeXt users <ntg-context@ntg.nl>, Richard
Mahoney | Indica et Buddhica <rmahoney@indica-et-buddhica.org>
Subject: Re: [NTG-context] Space after Round bracket before
Punctuation
Date: Thu, 9 Jul 2020 12:21:02 +0200
Mailer: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0)
Gecko/20100101
Thunderbird/68.10.0
X-Spam-Score: 0.0

On 7/9/2020 11:59 AM, Richard Mahoney | Indica et Buddhica wrote:
I'm typesetting some proceedings which include a good number of
round
brackets followed by punctuation. This often occurs in the body
of the
text, but also in the hand coded bibliographies, e.g.:

) plus . , ; :

The trouble is that excessive space is often introduced between the
bracket and the punctuation. I can control the excessive space that
sometimes occurs between ) and . by using )\periods[1], although this
ruins the protrusion if it occurs at the end of a line.

Does anyone know how I might be able to somehow "tie" ) to . , ; : so
that the distance remains reasonable, and so that protrusion still
works?
you first have to make an MWE that demonstrates how protrusion works 
here ... then we can see how we can best deal with it

Anyway, often tricks for this can be found in the test suite of font 
manual(s) ... here is a variant ...

\startluacode
     fonts.handlers.otf.addfeature {
         name     = "mykerns",
         type     = "kern",
         data     = {
             [")"] = {
                 [","] = -300,
                 ["."] = -300,
                 [":"] = -250,
                 [";"] = -250,
                 [")"] = -100,
             },
         },
     }
\stopluacode

\definefontfeature[default][default][mykerns=true]

\setupbodyfont [dejavu,12pt]

\startTEXpage[offset=10pt]
     whatever),
     whatever):
     whatever);
     whatever).
     whatever))
\stopTEXpage

Hans

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