Added some notes to the wiki: https://wiki.contextgarden.net/Featuresets#Open-type_features

On Sat, Mar 13, 2021 at 3:12 AM Hans Hagen <j.hagen@xs4all.nl> wrote:
On 3/13/2021 2:01 AM, Mohammad Hossein Bateni wrote:
> Umm... the fallbacks are correct.  My conclusion is that tlig does not
> work when the character is not in the font itself.  Is that the case? 
> Is this a bug or a feature?
>
> \starttext
>     
>   \definefontfallback[fall][dejavusansmono][0-0xfffff][check=yes,force=no]
>       \definefontsynonym[Test][file:Mikhak-Medium.ttf][fallbacks=fall]
>       \definefontfeature[tf][arabic][tlig=yes]
>       \definedfont[Test*tf]
>       foo--bar
>       [\char"2013]
>       [\char"2014]
> \stoptext
... or a misunderdstanding:

\starttext

\definefontfallback[myfallback][dejavuserif*default][0x02d,0x2013,0x2014][check=yes,force=yes]

\definefontsynonym[mytestfont][file:Mikhak-Medium.ttf][fallbacks=myfallback]
      \definedfont[mytestfont*arabic]
      foo--ofo---oof [\char"002D] [\char"2013] [\char"2014]
\stoptext

for a ligature to be made all the glyphs involved have to come from the
same font

I think you should wikify this (also because the font once complete is a
nice one to use in examples),

Hans


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