Solved with a dirty hack:
\startbuffer[text]
<p>A paragraph with a fraction made of text with styles:
<span class="fraction">a <i>fraction</i> made of text/with
<red><b>nested</b> styles</red> inside</span>.</p>
\stopbuffer
\startluacode
local gsub = string.gsub
local sfind = string.find
local xmlflush = lxml.flush
local startTextFraction = "$\\frac{\\text{"
local stopTextFraction = "}}$"
function xml.functions.textfraction( t )
local dt = t.dt
inspect( dt )
local wrapper
local slashfound = false
context( startTextFraction )
local index, child
for index, child in ipairs( dt ) do
if type( child ) == "string" then
if not slashfound and sfind( child, "/" ) then
context( gsub( child, "/", "}}{\\text{" ) )
slashfound = true
else
context( child )
end
elseif type( child ) == "table" then
wrapper = {
__parent__ = child.__parent__,
at = {},
dt = child
}
child.__parent__ = wrapper
xmlflush( wrapper )
end
end
context( stopTextFraction )
end
\stopluacode
\startxmlsetups xml:textsetups
\xmlsetsetup{#1}{*}{+}
\xmlsetsetup{#1}{p|i|b|red}{xml:*}
\xmlsetsetup{#1}{{span.fraction}}{xml:fraction}
\stopxmlsetups
\xmlregistersetup{xml:textsetups}
\startxmlsetups xml:p
\xmlflush{#1}\par
\stopxmlsetups
\startxmlsetups xml:i
{\it \xmlflush{#1}}
\stopxmlsetups
\startxmlsetups xml:red
{\red \xmlflush{#1}}
\stopxmlsetups
\startxmlsetups xml:b
{\bf \xmlflush{#1}}
\stopxmlsetups
\startxmlsetups xml:fraction
\xmlfunction{#1}{textfraction}
\stopxmlsetups
\starttext
\xmlprocessbuffer{main}{text}{}
\stoptext
Il 07/10/19 18:26, mf ha scritto:
Hello,
i'm using XML and i find useful specifying a fraction made of text this
way:
<span class="fraction">text for numerator/text for denominator</span>
With some lua, i can transform it into
\frac{\text{text for numerator}}{\text{text for denominator}}
which typesets something like this:
text for numerator
--------------------
text for denominator
Suppose you want to add some styling to the texts, like this:
<span class="fraction">text for <i>numerator</i>/text for
<b>denominator</b></span>
You should split the span node into two elements and the xmlflush them.
This is my M(not)WE:
\startbuffer[text]
<p>A paragraph with a fraction made of text with styles:
<span class="fraction">a <i>fraction</i> made of text/with
<red>styles</red> inside</span>.</p>
\stopbuffer
\startluacode
local sub = string.sub
local sfind = string.find
local xmltext = xml.text
local xmlconvert = xml.convert
local function numeratorDenominator( text )
local before, after = sfind( text, "[^<]/[^>]" )
local num, den
if before and after then
num = sub( text, 1, before )
den = sub( text, after )
end
return num, den
end
function xml.functions.textfraction( t )
local text = xmltext( t, '' )
local num, den = numeratorDenominator( text )
if num and den then
local fontstyle = tokens.getters.macro( "fontstyle" )
local xml_num = xmlconvert( num )
local xml_den = xmlconvert( den )
-- context( "$\\frac{\\text{\\" ..fontstyle .. " " .. num ..
"}}{\\text{\\" ..fontstyle .. " " .. den .. "}}$" )
context( "$\\frac{\\text{\\" ..fontstyle .. " " )
context( num ) -- context.xmlprocessstring( xml_num )
context( "}}{\\text{\\" ..fontstyle .. " " )
context( den ) -- context.xmlprocessstring( xml_den )
context( "}}$" )
else
context.xmlflush( t )
end
end
\stopluacode
\startxmlsetups xml:textsetups
\xmlsetsetup{#1}{*}{+}
\xmlsetsetup{#1}{p|i|red}{xml:*}
\xmlsetsetup{#1}{{span.fraction}}{xml:fraction}
\stopxmlsetups
\xmlregistersetup{xml:textsetups}
\startxmlsetups xml:p
\xmlflush{#1}\par
\stopxmlsetups
\startxmlsetups xml:i
{\it \xmlflush{#1}}
\stopxmlsetups
\startxmlsetups xml:red
{\red \xmlflush{#1}}
\stopxmlsetups
\startxmlsetups xml:fraction
\xmlfunction{#1}{textfraction}
\stopxmlsetups
\starttext
\xmlprocessbuffer{main}{text}{}
\stoptext
Massi
___________________________________________________________________________________
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
___________________________________________________________________________________