October 2021 - ntg-context - NTG Mailing Lists

new upload, new trickery
by Hans Hagen 16 Nov '21

16 Nov '21

Hi, Among the 'can they be made better' candidates in the engine are \vadjust and \local[left|right]box primitives that are not really used in context (okay, vadjust is used in mkii). The \vadjust vertical injector can be illustrated with \starttext \ignorespaces\input tufte \removeunwantedspaces we want a break before this line \vadjust pre {\break}% \ignorespaces\input tufte \removeunwantedspaces \page \ignorespaces\input tufte \removeunwantedspaces we want seperate lines now \leftparbox{\vadjust post {\break}}% \ignorespaces\input tufte \removeunwantedspaces \resetleftparbox{} \stoptext It's a signal that injects something in a vertical list without interupting the horizontal text flow. One can inject before (pre) or after (post which is default). New is that we can also influence the order: after vs before preceding \vadjust in the same line. Also new is that deeply nested adjustments can migrate (so the hole los: marks, inserts and vadjust are now in sync) which is demonstrated with the next example: \starttext \showstruts \input tufte \removeunwantedspaces\space \localleftbox par {% \hbox to 0pt{% \llap{L}% \vadjust{\strut\blackrule[width=1cm,color=red]}% \hbox{\vadjust pre{\strut\blackrule[width=1cm,color=green]}}% }\hss }% \localrightbox par {}% \input tufte \removeunwantedspaces\space \vadjust pre {\strut BEFORE 1}% \vadjust pre {\strut BEFORE 2}% \vadjust before {\strut AFTER 1}% \vadjust before {\strut AFTER 2}% \ignorespaces \input tufte \stoptext Indeed it looks bad (ugly) but it illustrates the idea. What makes vadjust sort of useless for content is that it messes up spacing (but if there is real demand and usage i can sort that out at some point, maybe some new options or so). Thsi example also brings us to local boxes: \showframe \starttext \showmakeup[hbox] \startnarrower[2*left] \raggedleft {\localleftbox par {L1}\input tufte \par} \stopnarrower \blank \startnarrower[2*middle] \raggedcenter {\localrightbox par {R1}\input tufte \par} \stopnarrower \blank \stoptext New is the par keyword that forces the setting to be applied from the first line downards (fyio: these commands, when display set registers, when inline they set registers and inject a node). Watch out: one needs to use grouping in order not to bleed into other mechanisms. Also new is that we can query the content of these registers using \the, as in: \dorecurse{10}{ \showboxes \localleftbox{\ruledhbox {\smallinfofont\setstrut\strut[L #1.0]}}% \localleftbox{\ruledhbox {\smallinfofont\setstrut\strut[L #1.1]}\the\localleftbox}% \localleftbox{\ruledhbox {\smallinfofont\setstrut\strut[L #1.2]}\the\localleftbox}% \localleftbox{\ruledhbox {\smallinfofont\setstrut\strut[L #1.3]}\the\localleftbox}% % \localrightbox{\ruledhbox {\smallinfofont\setstrut\strut[R #1.0]}}% \localrightbox{\the\localrightbox\ruledhbox{\smallinfofont\setstrut\strut[R #1.1]}}% \localrightbox{\the\localrightbox\ruledhbox{\smallinfofont\setstrut\strut[R #1.2]}}% \localrightbox{\the\localrightbox\ruledhbox{\smallinfofont[R #1.3]}}% % \localrightbox{}% \samplefile{tufte} } Flushing permits us to append and prepend but it's still ugly so that is why we now have a new interface (context layer on top of engine): \dorecurse{10}{ \showboxes % \resetleftparbox \resetrightparbox % \prependleftparbox {\ruledhbox{\smallinfofont\setstrut\strut[L #1.0]}}% \prependleftparbox {\ruledhbox{\smallinfofont\setstrut\strut[L #1.1]}}% \prependleftparbox {\ruledhbox{\smallinfofont\setstrut\strut[L #1.2]}}% \prependleftparbox {\ruledhbox{\smallinfofont\setstrut\strut[L #1.3]}}% % \appendrightparbox{\ruledhbox{\smallinfofont\setstrut\strut[R #1.0]}}% \appendrightparbox{\ruledhbox{\smallinfofont\setstrut\strut[R #1.1]}}% \appendrightparbox{\ruledhbox{\smallinfofont\setstrut\strut[R #1.2]}}% \appendrightparbox{\ruledhbox{\smallinfofont[R #1.3]}}% % \samplefile{tufte} } But as this is not really user friendly, there is more: a mechanism for hooking in handlers. \definelocalboxes [linenumber] [command=\LeftNumber, location=left, width=3em, style=\bs, color=darkred] \definelocalboxes [linenumbertwo] [linenumber] [command=\RightNumber, location=right, width=6em, style=\bf, color=darkgreen] \definelocalboxes [linetext] [command=\LeftText, location=lefttext, style=\bs, color=darkblue] \definelocalboxes [linetexttwo] [linetext] [command=\RightText, location=righttext, style=\bf, color=darkgray] % just using the content % \protected\def\LeftNumber {\hbox to \localboxesparameter{width}{\strut\box\localboxcontentbox\hss)}} % \protected\def\RightNumber{\hbox to \localboxesparameter{width}{\strut(\hss\box\localboxcontentbox)}} % using the provided line number: % \def\LineNumberL{\the\localboxlinenumber} % \def\LineNumberR{\the\localboxlinenumber} % using a tex counter % \newcount\MyLineNumberL % \newcount\MyLineNumberR % \def\LineNumberL{\global\advance\MyLineNumberL\plusone\the\MyLineNumberL} % \def\LineNumberR{\global\advance\MyLineNumberR\plusone\the\MyLineNumberR} % using proper counters \definecounter[MyLineNumberL] \definecounter[MyLineNumberR] \setupcounter[MyLineNumberL][numberconversion=characters] \setupcounter[MyLineNumberR][numberconversion=romannumerals] \def\LineNumberL{\incrementcounter[MyLineNumberL]\convertedcounter[MyLineNumberL]} \def\LineNumberR{\incrementcounter[MyLineNumberR]\convertedcounter[MyLineNumberR]} \protected\def\LeftNumber {\hbox to \localboxesparameter{width}{\strut(\LineNumberL\hss)}} \protected\def\RightNumber{\hbox to \localboxesparameter{width}{\strut(\hss\LineNumberR)}} \protected\def\LeftText #1{#1\quad} \protected\def\RightText#1{\quad#1} \showframe \starttext \start \localbox[linenumber]{}% \localbox[linenumbertwo]{}% \localbox[linetext]{L}% \startlocalbox[linetexttwo] R \stoplocalbox \dorecurse{100}{ \samplefile{tufte} \par } \stop If you play a bit with these low level mechanism the luametatex / context combination now permits weird applications (which for sure some of you will (ab)use). The above example shows how to implement line numbers (there are drawbacks compared to the existing mechanisms) and other stuff in the margins and text edges but the most important aspect is that when the content in these boxes has width, it will be taken into account in the par builder because that is what this is about: these local boxes are taken into acount when breaking lines. When the handlers kick in, you have \localboxattribute : more for internal use \localboxlinenumber : as the par builder sees it \localboxwidth : the local box width \localboxoffset : the total distance to the edge \localboxleftskip : the effective leftskip \localboxrightskip : the effective rightskip \localboxlefthang : the current shape related value \localboxrighthang : the current shape related value \localboxindent : only first line \localboxparfillleftskip : effective value (onky last line) \localboxparfillrightskip : effective value (only last line) \localboxovershoot : overfull compensation most of these relate to normalized lines and as such there is plenty to play with. Others can be seen in the examples. I might add some more control to both these 'injection' mechanism because directly out of the (pdftex/omega/luatex) they are not that useful (which is probably also why we don't use them.) These are cheap extensions so they don't really influence runtime much, so .. when not used ... no harm done. I really have no clue how useful this is. I need to ponder this usage: \definelocalboxes [linetextA] [command=\LeftTextA, location=lefttext, style=\bs, color=darkblue] \protected\def\LeftTextA#1{\llap{#1}\quad} \definelocalboxes [linetextB] [command=\LeftTextB, location=left, style=\bs, color=darkgreen] \protected\def\LeftTextB{\llap{\unhbox\localboxcontentbox}\quad} \starttext \dorecurse{10}{some text #1 } \leftparbox {\red \bf keyword}HERE\leftparbox{} \dorecurse{10}{some text #1 } \blank {\dorecurse{10}{some text #1 } \leftparbox {\red \bf keyword}test \dorecurse{10}{some text #1 }} \blank {\dorecurse{10}{some text #1 } \localbox[linetextA]{keyword}HERE \dorecurse{10}{some text #1 }} {\dorecurse{10}{some text #1 } \localbox[linetextB]{keyword}HERE \dorecurse{10}{some text #1 }} {\dorecurse{10}{some text #1 } \localbox[linetextB]{keyword 1}HERE1 \dorecurse{10}{some text #1 } \localbox[linetextB]{keyword 2}HERE2 \dorecurse{10}{some text #1 }} \stoptext so there's always so echallenge left. 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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Hyphenation on digits
by Jairo A. del Rio 03 Nov '21

03 Nov '21

Hi, list. I want to know if ConTeXt provides an option to automatically hyphenate/break digits as if they were alphabetic characters. Example, in a narrow page I expect something like that (I've used (-) for an optional hyphen): *π = *3.141592653(-) 58979323846264(-) 33832795028841(-) 97169399375105(-) ... I found myself unable to read a satisfactory solution in the mailing list archive nor other TeX related resources. Maybe LMTX has some magic for that? Cordially, Jairo

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\doifinstring: strange characters on the output
by Tomas Hala 02 Nov '21

02 Nov '21

Hi all, I noticed that \doifinstring produces quite strange output if a command follows immediately (or with any amount of spaces) after the substring I am searching for: -------------------------------------MWE \starttext \def\xxx{asdf \bf Z:\bf asdf} % strange \def\xxx{asdf \bf Z: \bf asdf} % strange \def\xxx{asdf \bf Z:: \bf asdf} % OK \def\xxx{asdf \bf Z: text \bf asdf} % OK \def\xxx{asdf \bf Z:{} \bf asdf} % OK \doifinstring{Z:}{\xxx}{yes!} \stoptext ----------------------------------OUTPUT fbf@yes! fbf@yes! yes! yes! yes! ---------------------------------------- If I insert another character, text or {} between them (with or without spaces), all is ok. I would like to ask what is the cause of this behavior and how to use the \doifinstring to prevent the "fbf@" on the output. Best wishes Tomáš

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Cannot access Lua function
by kauśika cittūr 01 Nov '21

01 Nov '21

Dear list, In one of my documents I have this lua block – \startluacode local metadata = lpdf.getmetadata(); ⋮ \stopluacode to modify some metadata fields. The file compiles with the latest LMTX (2021.10.28) without any errors but no PDF is produced. In the log, the following line is present : backend > blocked > function 'getmetadata' is not accessible I recall that this was working just fine some days back. Please advise. Thanks, kauśika

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SyncTeX setup
by Henning Hraban Ramm 01 Nov '21

01 Nov '21

Hi, has anyone a working SyncTeX setup with ConTeXt LMTX for anything else than TeXshop? With LaTeX, it works for me with Skim (+ Atom/Textadept/TeXworks) and TeXstudio. And in TeXshop we got our own parser. But can we expect others to adapt to our “superior” SyncTeX format? (I don’t understand the format yet and can’t tell what’s the difference.) Hraban

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\externafigure and \at do not work together
by a badin 01 Nov '21

01 Nov '21

Hello, perhaps this is how it is supposed to work, but: \externalfigure[clock.jpg][clock] \starttext \at[clock] refers to a clock \stoptext produces "?? refers to a clock", instead of "1 refers a clock" --- the wiki of \at says, that labels of figures can be refered to. Is this a bug, or can only some labels be refered to? I was able to fix it using: \reference[clock]{\externalfigure[clock.jpg]} \starttext \at[clock] refers to a clock \stoptext and \externalfigure[clock][] \starttext \at \stoptext produces an interesting artwork... so I thought maybe this could be a bug. LMTX 2021.10.21 Best, Andrej

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Bloody PDF boxes and cr*p marks!
by Henning Hraban Ramm 01 Nov '21

01 Nov '21

Comrades! There must have been a time when PDF boxes (i.e. CropBox, TrimBox, BleedBox) worked as they should, but it must have been a short time. The wiki page https://wiki.contextgarden.net/PDF_Boxes is mostly a documentation of bugs and workarounds, but even that is not entirely correct (any more?). I gave up on that subject and still fix the boxes with Acrobat Pro whenever I need them to be correct. But that’s no solution. (And it’s probably also my fault, since I was one of those who wanted this implemented and then didn’t check enough if it does what it should.) Ok, calm down, try again... * MediaBox is supposed to be the biggest, i.e. print sheet. * CropBox is the viewable area – usually same as MediaBox or TrimBox makes sense. * BleedBox must be TrimBox plus bleed. * ArtBox is neglectable for whole layouts (same as TrimBox might make sense), just interesting in \externalfigure. According to PDF Standard, MediaBox is the only required one; but CropBox is the most important one, since PDF viewers rely on it. With \setuppaper[A4] all boxes can be the same (or undefined). Status quo. With \setuppaper[A4][A4,oversized] I’d expect ConTeXt to set... * MediaBox and CropBox to the bigger format * TrimBox to the page format (A4) * BleedBox also to the page format, while no bleed is defined Status quo: no additional boxes defined. Beware, \showframe draws a green box at the paper size (supposed TrimBox), this is misleading in Acrobat Reader & Pro, where the TrimBox is shown in green (if this option is activated)! Bleed is to be defined in \setuplayout: \showframe \setuppapersize[A4][A4,oversized] \setuplayout[ location=middle, bleedoffset=-5mm, marking=on, ] %\setupinteractionscreen[width=max,height=max] \starttext X \stoptext Status quo: * works only with \setupinteractionscreen * bleedoffset must be negative * BleedBox is set, but not TrimBox (TB > BB is a nesting error) Beware, \setupbleeding refers only to stretching of images (\externalfigure)! This gives more or less correct results: \setuplayout[ location=middle, trimoffset=-7.5mm, bleedoffset=3mm, marking=on, ] * still works only with \setupinteractionscreen * negative trimoffset defines the TrimBox (actual page size), value is subtracted from sheet size. * positive bleedoffset (internally added to trimoffset) * to define trimoffset, I must know the difference between paper size and sheet size ("oversized" adds 15 mm). I.e. ConTeXt “thinks” from the sheet size instead from the (IMO more natural) paper size. For me, the more natural setup would be: \setuplayout[ trimoffset=0mm, % from the paper size outward bleedoffset=3mm, % same, independent of trimoffset ] % ... and no dependency on interactionscreen! So far, I ignored cropoffset. The parameter in itself works as I expected it to: cropoffset=3mm decreases the visible area by 3mm on each side. But it also moves the other boxes by that value! IMO that makes no sense, CropBox can be completely independent of the other boxes! It would be logical to use negative values here, since the size decreases, in opposite to my suggested handling of the other parameters. Yes, that would mean a backward incompatible change. But how many of us rely on the strange current behavior? Please let us fix this! In some cases it makes sense to have different values on e.g. inner and outer edges; I feat that would add a plethora of additional parameters (leftbleedoffset, innerbleedoffset...). Maybe give a list like in CSS? bleedoffset={3mm,3mm,3mm,0mm} – top, right, bottom, left order implied; not very “ConTeXt style”. Hraban

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PDF text stream with delimitedtext
by Adam Reviczky 30 Oct '21

30 Oct '21

Hi, I am trying to use quotation or blockquote in a document, but when selecting and copying the text in poppler/pdf.js I get double marks. Looking at the minimal example below: \nopdfcompression \setuppagenumbering[location=] \starttext \startquotation Hello world! \stopquotation \setupquotation[left=«,right=»] \startquotation Hello world! \stopquotation \setupquotation[left=‘,right=’] \startquotation Hello world! \stopquotation \setupdelimitedtext[blockquote][left=‘,right=’] \startblockquote Hello world! \stopblockquote “Hello world!”\\ «Hello world!»\\ ‘Hello world!’\\ \startquote Hello world! \stopquote\\ \quote{Hello world!}\\ \stoptext The text stream seems to have an additional object for the quotation and blockquote lines. Rendering the PDF in itself is fine but when copying the text I get mixed results (poppler/evince and pdf.js give double marks but mupdf does not: “Hello world!””,«Hello world!»»,‘Hello world!’’,‘Hello world!’’). Is this just an issue with poppler/pdf.js when trying to extract the text (as the PDF rendering seems all fine)? Adam

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getting number from context.figurewidth
by Pablo Rodriguez 28 Oct '21

28 Oct '21

Dear list, I have the following sample: \starttext \startluacode document.sample = "xml-mkiv.pdf" context.getfiguredimensions({ document.sample }) context(context.figureheight) context.par() context(tex.dimen.paperheight) \stopluacode \stoptext Is there a way that I can get a number from context.figureheight, such as I get it from tex.dimen.paperheight? Many thanks for your help, Pablo -- http://www.ousia.tk

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XML-processing: Error with hyphenatedurl
by denis.maier＠unibe.ch 27 Oct '21

27 Oct '21

Hi, I've receiving errors that seem to be related to hyphenatedurl. The problem is I cannot really reproduce it in a MWE. The example below works, but if I include the link in my real document, I'am getting this error message (copied from -error.log): %%%%%%%%%%%%%%%%%%%%% return { ["errortype"]=1, ["filename"]="", ["lastcontext"]="\n<to be read again> \n \n \\xdef<file://xdef> \n<macro> \\expanded<file://expanded> \n #1->\\xdef<file://xdef> \n \\m_syst_helpers_expanded<file://m_syst_helpers_expanded> {\\noexpand #1}\\m_syst_helpers_expanded \n<macro> \\22>:xml:ext-link<file://22%3e:xml:ext-link> \n #1->\\begingroup<file://begingroup> \\expandUx<file://expandUx> \\expanded<file://expanded> \n {\\goto {\\hyphenatedurl {\\xmlflush {#1}}}[url(\\xmlflush<file://xmlflush> {#1})]}\\endgroup \n<lua output> \n<macro> \\22>:xml:p<file://22%3e:xml:p> \n #1->\\begingroup<file://begingroup> \\xmlfilter<file://xmlfilter> {#1}{.[@xml:lang]/command(xml:language)}\\xmlflush {#1}\n \\endgroup<file://endgroup> \\par<file://par> \n<lua output> \n ...\n\n<initial> \n \n\n", ["lastluaerror"]="", ["lasttexerror"]="Missing number, treated as zero", ["lasttexhelp"]="A number should have been here; I inserted '0'. (If you can't figure out why I\nneeded to see a number, look up 'weird error' in the index to The TeXbook.)", ["linenumber"]=9, ["offset"]=10, ["skiplinenumber"]=5, } %%%%%%%%%%%%%%%%%%%% Two things seemed to make it work: 1. Remove the link. 2. Comment out \expandUx in this setup: %%%%%%%%%%%%%%%%%%%% \startxmlsetups xml:ext-link \begingroup \expandUx % commenting this out makes it work \expanded{\goto{\hyphenatedurl{\xmlflush{#1}}}[url(\xmlflush{#1})]} \endgroup \stopxmlsetups %%%%%%%%%%%%%%%%%%%% Best, Denis %%%%%%%%%%%%%%%%%%%%%%%%%%%% \setupinteraction[state=start] \startxmlsetups xml:test \xmlsetsetup{#1}{*}{-} \xmlsetsetup{#1}{article|ext-link}{xml:*} \stopxmlsetups \xmlregistersetup{xml:test} \startxmlsetups xml:article \starttext \xmlflush{#1} \stoptext \stopxmlsetups \startxmlsetups xml:ext-link \begingroup \expandUx \expanded{\goto{\hyphenatedurl{\xmlflush{#1}}}[url(\xmlflush{#1})]} \endgroup \stopxmlsetups \startbuffer[test] <?xml version="1.0" encoding="utf-8" ?> <article> asdf <ext-link ext-link-type="uri" xlink:href="asdf">asdf</ext-link> </article> \stopbuffer \xmlprocessbuffer{test}{test}{} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

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