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Diffstat (limited to 'doc/context/sources/general/manuals/luatex/luatex-modifications.tex')
| -rw-r--r-- | doc/context/sources/general/manuals/luatex/luatex-modifications.tex | 76 |
1 files changed, 68 insertions, 8 deletions
diff --git a/doc/context/sources/general/manuals/luatex/luatex-modifications.tex b/doc/context/sources/general/manuals/luatex/luatex-modifications.tex index 2857603ea..b5d8f2750 100644 --- a/doc/context/sources/general/manuals/luatex/luatex-modifications.tex +++ b/doc/context/sources/general/manuals/luatex/luatex-modifications.tex @@ -326,7 +326,7 @@ provide the ability to use content that has been rendered in several places, and images are also common. For that reason we also changed the names: \starttabulate[|l|l|] -\NC \bf new name \NC \bf old name \NC \NR +\BC new name \BC old name \NC \NR \NC \type {\saveboxresource} \NC \type {\pdfxform} \NC \NR \NC \type {\saveimageresource} \NC \type {\pdfximage} \NC \NR \NC \type {\useboxresource} \NC \type {\pdfrefxform} \NC \NR @@ -1063,20 +1063,58 @@ kerns, should be handled in the input or macro package because there is no way w can predict the expected behaviour. In fact, the \type {\linedir} is just a convenience extra which could also have been implemented using node list parsing. +Glue after a dir node is ignored in the linebreak decision but you can bypass that +by setting \type {\breakafterdirmode} to~\type {1}. The following table shows the +difference. Watch your spaces. + +\def\ShowSome#1{% + \BC + \type{#1} + \NC + \breakafterdirmode = 0 + \hsize 0pt + #1 + \NC + \NC + \breakafterdirmode = 1 + \hsize 0pt + #1 + \NC + \NC \NR \HL +} + +\starttabulate[|l|Tp(0pt)|w(5em)|Tp(0pt)|p|] + \HL + \BC \type{\breakafterdirmode} + \BC \type{0} + \NC + \BC \type{1} + \NC + \NC \NR + \HL + \ShowSome{pre {\textdir TLT xxx} post} + \ShowSome{pre {\textdir TLT xxx }post} + \ShowSome{pre{ \textdir TLT xxx} post} + \ShowSome{pre{ \textdir TLT xxx }post} + \ShowSome{pre { \textdir TLT xxx } post} + \ShowSome{pre {\textdir TLT\relax\space xxx} post} +\stoptabulate + + Another adaptation to the \ALEPH\ directional model is control over shapes driven by \type {\hangindent} and \type {\parshape}. This is controlled by a new parameter \type {\shapemode}: -\starttabulate[|cTB|c|] -\NC \NC \bf \type {\hangindent} \NC \bf \type {\parshape} \NC \NR -\NC 0 \NC normal \NC normal \NC \NR -\NC 1 \NC mirrored \NC normal \NC \NR -\NC 2 \NC normal \NC mirrored \NC \NR -\NC 3 \NC mirrored \NC mirrored \NC \NR +\starttabulate[|c|c|c|] +\BC \BC \type {\hangindent} \BC \type {\parshape} \NC \NR +\BC \type{0} \NC normal \NC normal \NC \NR +\BC \type{1} \NC mirrored \NC normal \NC \NR +\BC \type{2} \NC normal \NC mirrored \NC \NR +\BC \type{3} \NC mirrored \NC mirrored \NC \NR \stoptabulate The value is reset to zero (like \type {\hangindent} and \type {\parshape}) -after the paragraph is done with. You can use negative values to preven t +after the paragraph is done with. You can use negative values to prevent this. In \in {figure} [fig:shapemode] a few examples are given. @@ -1217,6 +1255,28 @@ previous code (that mostly used \type {getc} calls), it can be quite a bit faste \stopsubsection +\startsubsection[title=Tabs and spaces] + +We conform to the way other \TEX\ engines handle trailing tabs and spaces. For +decades trailing tabs and spaces (before a newline) were removed from the input +but this behaviour was changed in September 2017 to only handle spaces. We are +aware that this can introduce compatibility issues in existing workflows but +because we don't want too many differences with upstream \TEXLIVE\ we just follow +up on that patch (which is a functional one and not really a fix). It is up to +macro packages maintainers to deal with possible compatibility issues and in +\LUATEX\ they can do so via the callbacks that deal with reading from files. + +The previous behaviour was a known side effect and (as that kind of input +normally comes from generated sources) it was normally dealt with by adding a +comment token to the line in case the spaces and|/|or tabs were intentional and +to be kept. We are aware of the fact that this contradicts some of our other +choices but consistency with other engines and the fact that in \KPSE\ mode a +common file \IO\ layer is used can have a side effect of breaking compatibility. +We still stick to our view that at the log level we can (and might be) more +incompatible. + +\stopsubsection + \stopsection \stopchapter |