context.delayed as parameter of setuphead[before=...]
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Dear List, I'm trying to mirror the context command `\setuphead[chapter][before=hello]` into lua with delayed typesetting of 'hello', but `\ctxlua{context.setuphead({'chapter'}, {before=context.delayed'hello'})}` does not have any effect. Could anyone help me on this? Thanks! Best, Sylvain
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On the Lua side, you'll have to pass strings so your example works, as tables like those in setuphead({somehead}, {somesettings}) are actual Lua tables and follow Lua, not TeX, rules (see e.g. Lua reference in https://www.lua.org/manual/5.4/ or, better, CLD manual in http://www.pragma-ade.nl/general/manuals/cld-mkiv.pdf): \starttext \startluacode --First example for m = 1, 3 do context.setuphead({'chapter'}, {before='hello'}) context.startchapter({title="I'm a chapter!"}) for i = 1, 3 do context.input("knuth") end context.stopchapter() end --Second example --We'll pass some strings to TeX local nice = "ConTeXt is love, ConTeXt is life" local somehead = 'chapter' local sometext = 'vallejo-trilce-es' context.setuphead({somehead}, {before=nice}) context.startchapter({title=somehead}) context.input(sometext) context.stopchapter() \stopluacode \stoptext I hope examples help. Regards, Jairo :) El lun., 2 de nov. de 2020 a la(s) 21:09, Sylvain Hubert ( champignoom@gmail.com) escribió:
Dear List,
I'm trying to mirror the context command `\setuphead[chapter][before=hello]` into lua with delayed typesetting of 'hello', but `\ctxlua{context.setuphead({'chapter'}, {before=context.delayed'hello'})}` does not have any effect. Could anyone help me on this? Thanks!
Best, Sylvain
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maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net
___________________________________________________________________________________
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as tables like those in setuphead({somehead}, {somesettings}) are actual Lua tables and follow Lua, not TeX, rules But there are lua apis that support delayed TeX like `context.chapter(context.delayed'text')`. Whether or not the function is stored in a table should be theoretically irrelevant. I guess there should be a switch somewhere that let the command recognized delayed function.
On Tue, 3 Nov 2020 at 03:29, Jairo A. del Rio
On the Lua side, you'll have to pass strings so your example works, as tables like those in setuphead({somehead}, {somesettings}) are actual Lua tables and follow Lua, not TeX, rules (see e.g. Lua reference in https://www.lua.org/manual/5.4/ or, better, CLD manual in http://www.pragma-ade.nl/general/manuals/cld-mkiv.pdf):
\starttext
\startluacode
--First example
for m = 1, 3 do
context.setuphead({'chapter'}, {before='hello'})
context.startchapter({title="I'm a chapter!"})
for i = 1, 3 do
context.input("knuth")
end
context.stopchapter()
end
--Second example
--We'll pass some strings to TeX
local nice = "ConTeXt is love, ConTeXt is life"
local somehead = 'chapter'
local sometext = 'vallejo-trilce-es'
context.setuphead({somehead}, {before=nice})
context.startchapter({title=somehead})
context.input(sometext)
context.stopchapter()
\stopluacode
\stoptext
I hope examples help.
Regards,
Jairo :)
El lun., 2 de nov. de 2020 a la(s) 21:09, Sylvain Hubert ( champignoom@gmail.com) escribió:
Dear List,
I'm trying to mirror the context command `\setuphead[chapter][before=hello]` into lua with delayed typesetting of 'hello', but `\ctxlua{context.setuphead({'chapter'}, {before=context.delayed'hello'})}` does not have any effect. Could anyone help me on this? Thanks!
Best, Sylvain
___________________________________________________________________________________ If your question is of interest to others as well, please add an entry to the Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net
___________________________________________________________________________________
___________________________________________________________________________________ If your question is of interest to others as well, please add an entry to the Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net
___________________________________________________________________________________
![](https://secure.gravatar.com/avatar/23c65792d6f3eb5f6194f6ec9eadc2ac.jpg?s=120&d=mm&r=g)
Sorry. What I meant is: when you use context.setuphead({'chapter'}, {title="Some text"}) at the Lua end, {'chapter'} and {title="Some text"} (notice "Some text" is a string, not a function) are Lua tables. TeX will print "Some text", but it won't work for context.delayed as it is another table (metatable trickery to allow nesting, I guess). Try: \starttext \startluacode context(type(context.delayed)) \stopluacode \stoptext Long story short: context.cmda(context.delayed.cmdb(something)) will (possibly) work; context.cmdc({key=context.delayed.cmdd(somethingelse)}) won't. Hans and Wolfgang can elaborate in case I've missed something. Jairo :) El lun., 2 de nov. de 2020 a la(s) 22:06, Sylvain Hubert ( champignoom@gmail.com) escribió:
as tables like those in setuphead({somehead}, {somesettings}) are actual Lua tables and follow Lua, not TeX, rules But there are lua apis that support delayed TeX like `context.chapter(context.delayed'text')`. Whether or not the function is stored in a table should be theoretically irrelevant. I guess there should be a switch somewhere that let the command recognized delayed function.
On Tue, 3 Nov 2020 at 03:29, Jairo A. del Rio
wrote: On the Lua side, you'll have to pass strings so your example works, as tables like those in setuphead({somehead}, {somesettings}) are actual Lua tables and follow Lua, not TeX, rules (see e.g. Lua reference in https://www.lua.org/manual/5.4/ or, better, CLD manual in http://www.pragma-ade.nl/general/manuals/cld-mkiv.pdf):
\starttext
\startluacode
--First example
for m = 1, 3 do
context.setuphead({'chapter'}, {before='hello'})
context.startchapter({title="I'm a chapter!"})
for i = 1, 3 do
context.input("knuth")
end
context.stopchapter()
end
--Second example
--We'll pass some strings to TeX
local nice = "ConTeXt is love, ConTeXt is life"
local somehead = 'chapter'
local sometext = 'vallejo-trilce-es'
context.setuphead({somehead}, {before=nice})
context.startchapter({title=somehead})
context.input(sometext)
context.stopchapter()
\stopluacode
\stoptext
I hope examples help.
Regards,
Jairo :)
El lun., 2 de nov. de 2020 a la(s) 21:09, Sylvain Hubert ( champignoom@gmail.com) escribió:
Dear List,
I'm trying to mirror the context command `\setuphead[chapter][before=hello]` into lua with delayed typesetting of 'hello', but `\ctxlua{context.setuphead({'chapter'}, {before=context.delayed'hello'})}` does not have any effect. Could anyone help me on this? Thanks!
Best, Sylvain
___________________________________________________________________________________ If your question is of interest to others as well, please add an entry to the Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net
___________________________________________________________________________________
___________________________________________________________________________________ If your question is of interest to others as well, please add an entry to the Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net
___________________________________________________________________________________
___________________________________________________________________________________ If your question is of interest to others as well, please add an entry to the Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net
___________________________________________________________________________________
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On 11/3/2020 4:05 AM, Sylvain Hubert wrote:
as tables like those in setuphead({somehead}, {somesettings}) are actual Lua tables and follow Lua, not TeX, rules But there are lua apis that support delayed TeX like `context.chapter(context.delayed'text')`. Whether or not the function is stored in a table should be theoretically irrelevant. I guess there should be a switch somewhere that let the command recognized delayed function. all is possible but not all is reasonable to support .. adding layer upon layed doesn't make it more pretty
anyway, chapter (section) titles go tinto a toc table and storing lua delayed function definitions there makes not much sense Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl -----------------------------------------------------------------
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% Hans, sorry for having replied on the wrong channel before.
On Tue, 3 Nov 2020 at 09:03, Hans Hagen
On 11/3/2020 4:05 AM, Sylvain Hubert wrote:
as tables like those in setuphead({somehead}, {somesettings}) are actual Lua tables and follow Lua, not TeX, rules But there are lua apis that support delayed TeX like `context.chapter(context.delayed'text')`. Whether or not the function is stored in a table should be theoretically irrelevant. I guess there should be a switch somewhere that let the command recognized delayed function. all is possible but not all is reasonable to support .. adding layer upon layed doesn't make it more pretty
Indeed, but still it would be nice to have a complete and consistent interface between tex and lua unless it would harm the functionality.
anyway, chapter (section) titles go tinto a toc table and storing lua delayed function definitions there makes not much sense
It might be helpful in cases like alternative coloring. Writing
"function() local x=1; return function() x=1-x; return ({'black', 'gray'})[x] end end" can be way much easier for lua speakers than digging up a bunch of documentations to figure out whether it's implemented, or how it can be implemented in a language like TeX, or both which is worse. In such cases, it would also be much natural to write 'before=function()..' than 'before=\ctxlua{function()...}` unless, again, the former harms the functionality. Sylvain
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On 11/4/2020 4:53 PM, Sylvain Hubert wrote:
% Hans, sorry for having replied on the wrong channel before.
On Tue, 3 Nov 2020 at 09:03, Hans Hagen
mailto:j.hagen@xs4all.nl> wrote: On 11/3/2020 4:05 AM, Sylvain Hubert wrote: > > as tables like those in setuphead({somehead}, {somesettings}) are > actual Lua tables and follow Lua, not TeX, rules > But there are lua apis that support delayed TeX like > `context.chapter(context.delayed'text')`. > Whether or not the function is stored in a table should be theoretically > irrelevant. > I guess there should be a switch somewhere that let the command > recognized delayed function. all is possible but not all is reasonable to support .. adding layer upon layed doesn't make it more pretty
Indeed, but still it would be nice to have a complete and consistent interface between tex and lua unless it would harm the functionality.
it would harm performance because it involves parsing all values and also ways around cases where the title is "function" (lieral text).
anyway, chapter (section) titles go tinto a toc table and storing lua delayed function definitions there makes not much sense
It might be helpful in cases like alternative coloring. Writing "function() local x=1; return function() x=1-x; return ({'black', 'gray'})[x] end end" can be way much easier for lua speakers than digging up a bunch of documentations to figure out whether it's implemented, or how it can be implemented in a language like TeX, or both which is worse. In such cases, it would also be much natural to write 'before=function()..' than 'before=\ctxlua{function()...}` unless, again, the former harms the functionality.
Really? I have no clue what that function makec clearer than tex. And one still needs some documentation that explains what it does. Often there often is a pretty clean way to do it with less code. Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl -----------------------------------------------------------------
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again, sorry for replying on the wrong channel.
On Wed, 4 Nov 2020 at 17:35, Hans Hagen
it would harm performance because it involves parsing all values and also ways around cases where the title is "function" (lieral text).
I'm not sure I understand what you mean by literal text "function" here, but in any case isn't it a one-off <1ms cost to parse a function?
"function() local x=1; return function() x=1-x; return ({'black',
'gray'})[x] end end" can be way much easier for lua speakers than digging up a bunch of documentations to figure out whether it's implemented, or how it can be implemented in a language like TeX, or both which is worse. Really? I have no clue what that function makec clearer than tex. And one still needs some documentation that explains what it does.
Often there often is a pretty clean way to do it with less code.
For an experienced tex speaker, indeed. But for an average user who just wants to typeset a bit of fancy stuff, programming in tex is probably not the most pleasant thing to do and arguably not the most reasonable either in light of any modern language like lua. Sylvain
participants (3)
-
Hans Hagen
-
Jairo A. del Rio
-
Sylvain Hubert