# [NTG-context] define xml entity

Hans Hagen j.hagen at xs4all.nl
Tue Apr 3 09:20:14 CEST 2018

```On 4/3/2018 9:00 AM, dr. Hans van der Meer wrote:
> How do I define an xml entity like ä?
> Is there an \xml-operation for defining an entity?
> Such that I can say \xml{ABC}{an alphabet} for using &ABC; so that it
> produces “an alphabet”, for example.
You can find some in the test suite but it boils down to ...

\xmlsetentity{one}  {...}
\xmltexentity{sim}  {...}

or defining them in the preamble section of the xml file itself.

Entities are tricky. When they are used as abstraction you often want
them roundtrip while otherwise you might want them expanded. YOu can
have double escaped entities (which can result from import/export in
half clever or inconsistent databases).  There's all kinds of control in
context.

Another tricky thing is that because tex doesn't like # etc we need to
have our own 'escapes' as well, so that runs in parallel of the
subsystem that carries (unexpanded) entities around.

It's a conceptual mess deel down ... (well, you can read/understand lua
so ...).

Hans

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