Re: cld questions

[Hans Hagen via ntg-context <ntg-context@ntg.nl>]

On 9/5/2021 12:01 PM, Henning Hraban Ramm via ntg-context wrote:
> Hi again,
> I’m converting a few macros into Lua (LMTX), but couldn’t find some answers in the docs:
> 
> 
> * How translates \ifodd\realpageno ?
> 
> This doesn’t work:
> if ((tex.getcount("realpageno") mod 2) == 1) then
>   a = 1
> end

we're talking lua: 9 % 2 == 0

> TeX:
> \def\Something{1cm}
> 
> Lua:
> context.Something()

yes (assuming you're in scope)

  * TeX primitives
> Is tex.strut and tex.par supposed to work? Or how should I access these?

\strut is not is primitive

context.strut() and context.par() should just work

> 0) I don’t understand what “permanent” does and why I should maybe disable it. (cld-mkiv, p.146)

overload protection

\permanent\def\Whatever{?}
\overloadmode=0
%\overloadmode=3
%\overloadmode=4
\def\Whatever{!}

try 3 and 4 (actually, try to run your documents with overloadmode set 
and you might see where you replace core macros)

%enabledirectives[overloadmode=warning]
\enabledirectives[overloadmode=error]

btw, you can temporary do

\pushoverloadmode
potentially risky definitions
\popoverloadmode

> 1) The parameter y is actually supposed to be a dimension, but if I declare it "dimen", ConTeXt says there wasn’t a number at "1cm".
>     Or is a measure like that not a dimension?

if you want to use {} around it use "dimenargument"

> 2) The original interface of \MyFun had two optional parameters. I couldn’t find how to do that with interfaces.implement.
>     cld-mkiv, p.151 (12.7) shows how to do lists or key=value, but not single optional args.

there is "optional"

and ... cld is not yet updated to lmtx in this respect so some newer 
features are missing

Hans

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                                           Hans Hagen | PRAGMA ADE
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