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




-----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
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On 7/9/2020 11:59 AM, Richard Mahoney | Indica et Buddhica wrote:
> I'm typesetting some proceedings which include a good number of
> roundbrackets followed by punctuation. This often occurs in the body
> of thetext, but also in the hand coded bibliographies, e.g.:
> ) plus . , ; :
> The trouble is that excessive space is often introduced between
> thebracket and the punctuation. I can control the excessive space
> thatsometimes occurs between ) and . by using )\periods[1], although
> thisruins the protrusion if it occurs at the end of a line.
> Does anyone know how I might be able to somehow "tie" ) to . , ; :
> sothat the distance remains reasonable, and so that protrusion
> stillworks?
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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Richard Mahoney | Indica et Buddhica
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