NAME
====

xml-highlight - Highlight syntax in XML documents

SYNOPSIS
========

    xml-highlight [options] [<document>...]

DESCRIPTION
===========

The *xml-highlight* tool adds syntax highlighting to program listings in
an XML document. By default this is accomplished by wrapping detected
syntax in XSL-FO inline elements with the proper namespace to allow a
stylesheet to pass them through to the final FO processor. The actual
elements used can be customized, however.

To enable highlighting on text in an element, include the processing
instruction `<?language ...?>` in the element, where `...` is the name
of the language.

OPTIONS
=======

-c, --classes &lt;classes&gt;  
Use a custom class definitions file.

-f, --overwrite  
Overwrite input XML file(s) instead of outputting to stdout.

-h, -?, --help  
Show help/usage message.

-s, --syntax &lt;syntax&gt;  
Use a custom syntax definitions file.

--version  
Show version information.

In addition, the following options allow configuration of the XML
parser:

--dtdload  
Load the external DTD.

--huge  
Remove any internal arbitrary parser limits.

--net  
Allow network access to load external DTD and entities.

--noent  
Resolve entities.

--xinclude  
Do XInclude processing.

--xml-catalog &lt;file&gt;  
Use an XML catalog when resolving entities. Multiple catalogs may be
loaded by specifying this option multiple times.

CLASS FILE FORMAT
=================

The following describes the format of the custom class file specified
with -c.

Classes
-------

*Markup element:* &lt;`classes`&gt;

*Attributes:*

-   None

*Child elements:*

-   &lt;`class`&gt;

Class
-----

Represents a type of syntax and how it should be highlighted. This
element can also occur within the `syntax` element or within a
particular `language` element, in which case it is specific to that
language.

*Markup element:* &lt;`class`&gt;

*Attributes:*

-   `id`, the identifier of the class.

*Child elements:*

The element `class` contains one child element of any kind, which any
matching syntax will be wrapped in to.

Example custom classes file
---------------------------

    <classes xmlns:fo="http://www.w3.org/1999/XSL/Format">
    <class id="type">
    <fo:inline color="green"/>
    </class>
    <class id="control">
    <fo:inline color="blue"/>
    </class>
    <class id="string">
    <fo:inline color="red"/>
    </class>
    <class id="comment">
    <fo:inline color="pink"/>
    </class>
    </classes>

SYNTAX FILE FORMAT
==================

The following describes the format of the custom syntax file specified
with -s.

Syntax
------

*Markup element:* &lt;`syntax`&gt;

*Attributes:*

-   None

*Child elements:*

-   `class`

-   `language`

Language
--------

Describes the syntax of a particular language.

*Markup element:* &lt;`language`&gt;

*Attributes:*

-   `name`, the identifier of the language.

-   `caseInsensitive`, indicates whether keywords are case-insensitive
    in this language, with one of the following values:

    -   `"no"` - Keywords are case-sensitive (default)

    -   `"yes"` - Keywords are case-insensitive

*Child elements:*

-   &lt;`class`&gt;

-   &lt;`area`&gt;

-   &lt;`keyword`&gt;

Area
----

Matches a section of delimited text, such as strings, comments, etc.

*Markup element:* &lt;`area`&gt;

*Attributes:*

-   `start`, the opening delimiter.

-   `end`, the closing delimiter.

-   `class`, reference to the `class` element to use for this area.

*Child elements:*

If attribute `class` is not used, this element can contain one element
of any kind, in which the text matching the area will be wrapped.

Keyword
-------

Matches a particular keyword.

*Markup element:* &lt;`keyword`&gt;

*Attributes:*

-   `match`, the keyword to match.

-   `class`, reference to the `class` element to use for this keyword.

*Child elements:*

If attribute `class` is not used, this element can contain one element
of any kind, in which the text matching the keyword will be wrapped.

Example custom syntax file
--------------------------

    <syntax>
    <language name="c">
    <area start="&quot;" end="&quot;" class="string"/>
    <area start="/*" end="*/" class="comment"/>
    <keyword match="if" class="control"/>
    <keyword match="else" class="control"/>
    <keyword match="int" class="type"/>
    <keyword match="char" class="type"/>
    </language>
    </syntax>

BUILT-IN LANGUAGES
==================

The following is a list of language syntaxes currently built-in to the
tool:

-   c

-   csharp

-   go

-   java

-   javascript

-   pascal

-   python

-   ruby

-   rust

-   sh

-   sql

-   xml

-   xsl