# [luatex] kerning with delimiters with opentype math fonts

Hans Hagen pragma at wxs.nl
Sun Feb 19 13:24:08 CET 2017

On 2/18/2017 6:25 PM, Ulrike Fischer wrote:
> Am Sat, 18 Feb 2017 16:12:35 +0100 schrieb Hans Hagen:
>
>
>> It's a font issue
>
> Why does one get the faulty spacing only with \left/right? E.g. in
> this context version only the first is wrong:
>
> \starttext
>
> $\left|T \right|$ $|T|$
>
> \stoptext

italic correction is between characters and a \right is a fence and more
a construct where the inter-whatever spacing + staircase kerns apply so
it boils a bit down to what a sequence of chars is (for instance a \left
\right delimiter is an extensible character and as such not really a
character

it's a bit of a fuzzy area (i've seen different specs over time) ... of
course i can think of some more control options in the engine

(the problem is that at one time i had code in context that analyzed
this and acted upon it correcting the engine but then inconsistent fonts
show up and one has to make choices)

Hans

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