nixos: Split paras by \n\n in option descriptions
What annoyed me for a long time was the fact, that in order to break into a new paragraph, you need to insert </para><para> in the description attribute of an option. Now we will automatically create <para/> elements for every block that is separated by two consecutive newlines. I first tried to do this within options-to-docbook.xsl, but it turns out[1] that this isn't directly possible with XSLT 1.0, so I added another XSLT file that postprocesses the option descriptions that are now enclosed in <nixos:option-description/> by options-to-docbook.xsl. The splitting itself is a bit more involved, because we can't simply split on every \n\n because we'd also split text nodes of elements, for example: <screen><![CDATA[ one line another one ]]></screen> This would create one <para/> element for "one line" and another for "another line", which we obviously don't want because <screen/> is used to display verbatim contents of what a user is seeing on the screen. So what we do instead is splitting *only* the top-level text nodes within the outermost <para/> and leave all elements as-is. If there are more than one <para/> elements at the top-level, we simply don't process it at all, because the description then already contains </para><para>. https://www.mhonarc.org/archive/html/xsl-list/2012-09/msg00319.html Signed-off-by: aszlig <aszlig@nix.build> Cc: @edolstra, @domenkozar
This commit is contained in:
parent
953b77f07b
commit
f865d0feab
@ -90,7 +90,9 @@ let
|
||||
fi
|
||||
${buildPackages.libxslt.bin}/bin/xsltproc \
|
||||
--stringparam revision '${revision}' \
|
||||
-o $out ${./options-to-docbook.xsl} $optionsXML
|
||||
-o intermediate.xml ${./options-to-docbook.xsl} $optionsXML
|
||||
${buildPackages.libxslt.bin}/bin/xsltproc \
|
||||
-o "$out" ${./postprocess-option-descriptions.xsl} intermediate.xml
|
||||
'';
|
||||
|
||||
sources = lib.sourceFilesBySuffices ./. [".xml"];
|
||||
|
@ -4,6 +4,7 @@
|
||||
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
|
||||
xmlns:str="http://exslt.org/strings"
|
||||
xmlns:xlink="http://www.w3.org/1999/xlink"
|
||||
xmlns:nixos="tag:nixos.org"
|
||||
xmlns="http://docbook.org/ns/docbook"
|
||||
extension-element-prefixes="str"
|
||||
>
|
||||
@ -30,10 +31,12 @@
|
||||
|
||||
<listitem>
|
||||
|
||||
<para>
|
||||
<xsl:value-of disable-output-escaping="yes"
|
||||
select="attr[@name = 'description']/string/@value" />
|
||||
</para>
|
||||
<nixos:option-description>
|
||||
<para>
|
||||
<xsl:value-of disable-output-escaping="yes"
|
||||
select="attr[@name = 'description']/string/@value" />
|
||||
</para>
|
||||
</nixos:option-description>
|
||||
|
||||
<xsl:if test="attr[@name = 'type']">
|
||||
<para>
|
||||
|
115
nixos/doc/manual/postprocess-option-descriptions.xsl
Normal file
115
nixos/doc/manual/postprocess-option-descriptions.xsl
Normal file
@ -0,0 +1,115 @@
|
||||
<?xml version="1.0"?>
|
||||
|
||||
<xsl:stylesheet version="1.0"
|
||||
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
|
||||
xmlns:str="http://exslt.org/strings"
|
||||
xmlns:exsl="http://exslt.org/common"
|
||||
xmlns:db="http://docbook.org/ns/docbook"
|
||||
xmlns:nixos="tag:nixos.org"
|
||||
extension-element-prefixes="str exsl">
|
||||
<xsl:output method='xml' encoding="UTF-8" />
|
||||
|
||||
<xsl:template match="@*|node()">
|
||||
<xsl:copy>
|
||||
<xsl:apply-templates select="@*|node()" />
|
||||
</xsl:copy>
|
||||
</xsl:template>
|
||||
|
||||
<xsl:template name="break-up-description">
|
||||
<xsl:param name="input" />
|
||||
<xsl:param name="buffer" />
|
||||
|
||||
<!-- Every time we have two newlines following each other, we want to
|
||||
break it into </para><para>. -->
|
||||
<xsl:variable name="parbreak" select="'

'" />
|
||||
|
||||
<!-- Similar to "(head:tail) = input" in Haskell. -->
|
||||
<xsl:variable name="head" select="$input[1]" />
|
||||
<xsl:variable name="tail" select="$input[position() > 1]" />
|
||||
|
||||
<xsl:choose>
|
||||
<xsl:when test="$head/self::text() and contains($head, $parbreak)">
|
||||
<!-- If the haystack provided to str:split() directly starts or
|
||||
ends with $parbreak, it doesn't generate a <token/> for that,
|
||||
so we are doing this here. -->
|
||||
<xsl:variable name="splitted-raw">
|
||||
<xsl:if test="starts-with($head, $parbreak)"><token /></xsl:if>
|
||||
<xsl:for-each select="str:split($head, $parbreak)">
|
||||
<token><xsl:value-of select="node()" /></token>
|
||||
</xsl:for-each>
|
||||
<!-- Something like ends-with($head, $parbreak), but there is
|
||||
no ends-with() in XSLT, so we need to use substring(). -->
|
||||
<xsl:if test="
|
||||
substring($head, string-length($head) -
|
||||
string-length($parbreak) + 1) = $parbreak
|
||||
"><token /></xsl:if>
|
||||
</xsl:variable>
|
||||
<xsl:variable name="splitted"
|
||||
select="exsl:node-set($splitted-raw)/token" />
|
||||
<!-- The buffer we had so far didn't contain any text nodes that
|
||||
contain a $parbreak, so we can put the buffer along with the
|
||||
first token of $splitted into a para element. -->
|
||||
<para xmlns="http://docbook.org/ns/docbook">
|
||||
<xsl:apply-templates select="exsl:node-set($buffer)" />
|
||||
<xsl:apply-templates select="$splitted[1]/node()" />
|
||||
</para>
|
||||
<!-- We have already emitted the first splitted result, so the
|
||||
last result is going to be set as the new $buffer later
|
||||
because its contents may not be directly followed up by a
|
||||
$parbreak. -->
|
||||
<xsl:for-each select="$splitted[position() > 1
|
||||
and position() < last()]">
|
||||
<para xmlns="http://docbook.org/ns/docbook">
|
||||
<xsl:apply-templates select="node()" />
|
||||
</para>
|
||||
</xsl:for-each>
|
||||
<xsl:call-template name="break-up-description">
|
||||
<xsl:with-param name="input" select="$tail" />
|
||||
<xsl:with-param name="buffer" select="$splitted[last()]/node()" />
|
||||
</xsl:call-template>
|
||||
</xsl:when>
|
||||
<!-- Either non-text node or one without $parbreak, which we just
|
||||
want to buffer and continue recursing. -->
|
||||
<xsl:when test="$input">
|
||||
<xsl:call-template name="break-up-description">
|
||||
<xsl:with-param name="input" select="$tail" />
|
||||
<!-- This essentially appends $head to $buffer. -->
|
||||
<xsl:with-param name="buffer">
|
||||
<xsl:if test="$buffer">
|
||||
<xsl:for-each select="exsl:node-set($buffer)">
|
||||
<xsl:apply-templates select="." />
|
||||
</xsl:for-each>
|
||||
</xsl:if>
|
||||
<xsl:apply-templates select="$head" />
|
||||
</xsl:with-param>
|
||||
</xsl:call-template>
|
||||
</xsl:when>
|
||||
<!-- No more $input, just put the remaining $buffer in a para. -->
|
||||
<xsl:otherwise>
|
||||
<para xmlns="http://docbook.org/ns/docbook">
|
||||
<xsl:apply-templates select="exsl:node-set($buffer)" />
|
||||
</para>
|
||||
</xsl:otherwise>
|
||||
</xsl:choose>
|
||||
</xsl:template>
|
||||
|
||||
<xsl:template match="nixos:option-description">
|
||||
<xsl:choose>
|
||||
<!--
|
||||
Only process nodes that are comprised of a single <para/> element,
|
||||
because if that's not the case the description already contains
|
||||
</para><para> in between and we need no further processing.
|
||||
-->
|
||||
<xsl:when test="count(db:para) > 1">
|
||||
<xsl:apply-templates select="node()" />
|
||||
</xsl:when>
|
||||
<xsl:otherwise>
|
||||
<xsl:call-template name="break-up-description">
|
||||
<xsl:with-param name="input"
|
||||
select="exsl:node-set(db:para/node())" />
|
||||
</xsl:call-template>
|
||||
</xsl:otherwise>
|
||||
</xsl:choose>
|
||||
</xsl:template>
|
||||
|
||||
</xsl:stylesheet>
|
Loading…
Reference in New Issue
Block a user