# [dev-context] \lastxpos and \lastypos should behave like registers

Hans Hagen j.hagen at xs4all.nl
Thu May 23 01:55:09 CEST 2019

```On 5/23/2019 1:47 AM, Henri Menke wrote:
>
>
> On 23/05/19 11:36 AM, Hans Hagen wrote:
>> On 5/23/2019 1:11 AM, Henri Menke wrote:
>>> Dear devs,
>>>
>>> The two macros \lastxpos and \lastypos should behave like registers,
>>> because that is what they are in LuaTeX.  The following MWE fails with
>>>
>>> ! You can't use `the character 0' after \the
>>>
>>> \starttext
>>> \the\lastxpos
>>> \the\lastypos
>>> \stoptext
>>>
>>> A simple fix would be to wrap the macro in \numexpr like in the attached
>>> patch.
>>
>> hm, i was actually about to drop them completely ... anyway, i have no
>> problem with the fix but then it also need to be \unexpanded
>>    (i'm reshuffling some code so probably no beta for a few days)
>
> Dropping \pdflastxpos and \pdflastypos would break TikZ, so it would be
> good if at least the \lastxpos and \lastypos primitives would be
> accessible.
ok, but i assume that there is no need for the \pdf* ones (because i
decided to drop all those specific \pdf* aliases in the next beta ...
they were never meant to be persistent part of mkiv) ... i grepped tikz
and could not find usage of \pdf... apart from the official luatex ones

(actually, tikz is the only package i know that we need to keep an eye
on wrt downward compatibility; context modules use different interfaces)

Hans

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