Version 7 (modified by trac, 3 years ago) (diff)


Trac Macros

Trac macros extend Trac with custom functionality. Macros are a special type of plugin and are written in Python. A macro generates HTML in any context supporting WikiFormatting.

The macro syntax is [[macro-name(optional-arguments)]].

WikiProcessors are another kind of macro, commonly used for source code highlighting using a processor like !#python or !#apache:


Using Macros

Macro calls are enclosed in double-square brackets [[..]]. Like Python functions macros can have arguments, which take the form of a comma separated list within parentheses [[..(,)]]. A common macro used is a list of the 3 most recent changes to a wiki page, or here, for example, all wiki pages starting with 'Trac':

Wiki Markup Display

Getting Detailed Help

The list of available macros and the full help can be obtained using the MacroList macro, see below.

A brief list can be obtained via [[MacroList(*)]] or [[?]].

Detailed help on a specific macro can be obtained by passing it as an argument to MacroList, e.g. [[MacroList(MacroList)]], or more conveniently, by appending a question mark (?) to the macro's name, like in [[MacroList?]].

Available Macros

Inserts a list of all wiki pages with links to the page where this macro is used.

Accepts a page name as a parameter: if provided, pages that link to the provided page name are listed instead.


Inserts a menu with a list of all wiki pages with links to the page where this macro is used.

Accepts a page name as a parameter: if provided, pages that link to the provided page name are listed instead.


A macro to display list of posts and extracts outside (or inside) the Blog module - most commonly Wiki pages.

All arguments are optional:


Available named arguments:

  • recent= - max. number of posts
  • category= - a category
  • author= - an author
  • period= - time period of the format YYYY/MM
  • heading= - a heading for the list
  • format= - type of display (see below for details)
  • max_size= - max. number of characters to render for each post
  • meta= - use =off to hide date, author and categories (default 'on')

Example showing some available named arguments:

[[BlogList(recent=5, max_size=250, period=2007/12, author=osimons, format=float, heading=Some Trac Posts)]]

The arguments for criteria are 'AND'-based, so the above example will render at most 5 posts by 'osimons' in December 2007.

There is no heading unless specified.

Without restriction on recent number of posts, it will use the number currently active in the Blog module as default for 'float' and 'full' rendering, but for rendering of 'inline' list it will render all found as default unless restricted. Additionally for 'float' and 'full' it will truncate content if it is larger than a max_size (if set).

The format= keyword argument supports rendering these formats:

format=inlineRenders an unordered list in the normal text flow (default).
format=floatA floating box out on the side of the page with slightly more detail.
format=fullFull rendering like on period, category and author listings inside blog.

The arguments can appear in any order.

Posts are rendered sorted by newest first for all modes.


Write repository change log to output.

The ChangeLog macro writes a log of the last changes of a repository at a given path. Following variants are possible to use:

1. [[ChangeLog([reponame:]path)]]
2. [[ChangeLog([reponame:]path@rev)]]
3. [[ChangeLog([reponame:]path@rev, limit)]]
4. [[ChangeLog([reponame:]path@from-to)]]
5. [[ChangeLog([reponame:]path, limit, rev)]]
  1. Default repository is used if reponame is left out. To show the last five changes of the default repository:
    To show the last five changes of the trunk folder in a named repo:
  2. The ending revision can be set. To show the last five changes up to revision 99:
  3. The limit can be set by an optional parameter. To show the last 10 changes, up to revision 99:
    [[ChangeLog(otherrepo:/trunk@99, 10)]]
  4. A range of revisions can be logged.
    To lists all changes:
    HEAD can be left out:
  5. For backwards compatibility, revision can be stated as a third parameter:
    [[ChangeLog(otherrepo:/trunk, 10, 99)]]

limit and rev may be keyword arguments.

[[ChangeLog(otherrepo:/trunk, limit=10, rev=99)]]


Render a code example box that supports syntax highlighting. It support three types of examples: simple, correct, and incorrect. The SELECT ALL link highlights all of the code in the box to simplify the copy and paste action.

The simple example:

def get_templates_dirs():
    """ Notify Trac about templates dir. """
    from pkg_resources import resource_filename
    return [resource_filename(__name__, 'templates')]

will be rendered as:


The incorrect example:

## type = bad
fibs = 0 : 1 : [ a + b | a <- fibs | b <- tail fibs ]

will be rendered as:


The correct example:

## type = good
fibs = 0 : 1 : zipWith (+) fibs (tail fibs)

will be rendered as:


There is also support for getting sources from the repository:

## path=GPGMail/Source/GPGMailPreferences.m
## regex=".*updater\s*{"
## lines=3

will be rendered as:



  • type - (optional) a type of the example: simple (default), good, bad
  • title - (optional) the title of the example
  • path - (optional) a file in the repository (using TracLinks format for source code)
  • repo - (optional) repository to use (Trac 0.12 and upper only)
  • regex - (optional) a regular expression indicates where to start an example
  • lines - (optional) number of lines to show


Aliases: [[ListDownloads]]


Provides test macro for the tracextracturl.extract_url function.

This macro is intended for code testing by the developers of the above function and has no real usage for normal Trac users.

Macro usage: [[ExtractUrl(traclink)]]
Result: The URL extracted by extract_url

$Id: 17115 2018-04-12 21:50:07Z rjollos $

Description for extract_url()

Extracts an URL from an Wiki link, e.g. to used in macro produced HTML code.


$Id: 17115 2018-04-12 21:50:07Z rjollos $


Returns an (possible relative) URL which can be used in HTML code.

If raw is true the returned link will point to a downloadable version of the linked resource otherwise the same link is returned which would be used in the resulting Wiki page.

The raw links are also usable as online resouces, e.g. if the link target is to be used as input for a flash application etc.



from tracextracturl import extract_url
# ...
  url = extract_url(env, context, wikilink, raw=False)

Inside WikiMacros:

from tracextracturl import extract_url

def MyMacro(WikiMacroBase):
  def expand_macro (self, formatter, name, content):
     # e.g. wikilink = 'wiki:WikiStart' or 'attachment:file.ext'
     url = extract_url(self.env, formatter.context, wikilink)
     rawurl = extract_url(self.env, formatter.context, wikilink, True)


Inside a Trac macro called from the wiki page 'ExamplePage' of project 'project1' on a multi-project trac server:

    extract_url(self.env, formatter, 'attachment:file.js', True)

will return /project1/raw-attachment/wiki/ExamplePage/file.js, which could be directly accessed by the browser inside some javascript or flash HTML object code produced by the macro.


Embed an image in wiki-formatted text.

The first argument is the file specification. The file specification may reference attachments in three ways:

  • module:id:file, where module can be either wiki or ticket, to refer to the attachment named file of the specified wiki page or ticket.
  • id:file: same as above, but id is either a ticket shorthand or a Wiki page name.
  • file to refer to a local attachment named 'file'. This only works from within that wiki page or a ticket.

The file specification may also refer to:

  • repository files, using the source:file syntax (source:file@rev works also).
  • files, using direct URLs: /file for a project-relative, //file for a server-relative, or http://server/file for absolute location. An InterWiki prefix may be used.
  • embedded data using the rfc2397 data URL scheme, provided the URL is enclosed in quotes.

The remaining arguments are optional and allow configuring the attributes and style of the rendered <img> element:

  • digits and unit are interpreted as the size (ex. 120px, 25%) for the image
  • right, left, center, top, bottom and middle are interpreted as the alignment for the image (alternatively, the first three can be specified using align=... and the last three using valign=...)
  • link=some TracLinks... replaces the link to the image source by the one specified using a TracLinks. If no value is specified, the link is simply removed.
  • inline specifies that the content generated be an inline XHTML element. By default, inline content is not generated, therefore images won't be rendered in section headings and other one-line content.
  • nolink means without link to image source (deprecated, use link=)
  • key=value style are interpreted as HTML attributes or CSS style indications for the image. Valid keys are:
    • align, valign, border, width, height, alt, title, longdesc, class, margin, margin-(left,right,top,bottom), id and usemap
    • border, margin, and margin-* can only be a single number (units are pixels).
    • margin is superseded by center which uses auto margins


[[Image(photo.jpg)]]               # simplest
[[Image(photo.jpg, 120px)]]        # with image width size
[[Image(photo.jpg, right)]]        # aligned by keyword
[[Image(photo.jpg, nolink)]]       # without link to source
[[Image(photo.jpg, align=right)]]  # aligned by attribute

You can use an image from a wiki page, ticket or other module.

[[Image(OtherPage:foo.bmp)]]    # from a wiki page
[[Image(base/sub:bar.bmp)]]     # from hierarchical wiki page
[[Image(#3:baz.bmp)]]           # from another ticket
[[Image(ticket:36:boo.jpg)]]    # from another ticket (long form)
[[Image(source:/img/bee.jpg)]]  # from the repository
[[Image(htdocs:foo/bar.png)]]   # from project htdocs dir
[[Image(shared:foo/bar.png)]]   # from shared htdocs dir (since 1.0.2)

Adapted from the macro created by Shun-ichi Goto <gotoh@…>


Provide a list of known InterTrac prefixes.


Provide a description list for the known InterWiki prefixes.


List all known mime-types which can be used as WikiProcessors.

Can be given an optional argument which is interpreted as mime-type filter.


Display a list of all installed Wiki macros, including documentation if available.

Optionally, the name of a specific macro can be provided as an argument. In that case, only the documentation for that macro will be rendered.

Note that this macro will not be able to display the documentation of macros if the PythonOptimize option is enabled for mod_python!


Display a structural outline of the current wiki page, each item in the outline being a link to the corresponding heading.

This macro accepts four optional parameters:

  • The first is a number or range that allows configuring the minimum and maximum level of headings that should be included in the outline. For example, specifying "1" here will result in only the top-level headings being included in the outline. Specifying "2-3" will make the outline include all headings of level 2 and 3, as a nested list. The default is to include all heading levels.
  • The second parameter can be used to specify a custom title (the default is no title).
  • The third parameter selects the style of the outline. This can be either inline or pullout (the latter being the default). The inline style renders the outline as normal part of the content, while pullout causes the outline to be rendered in a box that is by default floated to the right side of the other content.
  • The fourth parameter specifies whether the outline is numbered or not. It can be either numbered or unnumbered (the former being the default). This parameter only has an effect in inline style.


List all pages that have recently been modified, ordered by the time they were last modified.

This macro accepts two ordered arguments and a named argument. The named argument can be placed in any position within the argument list.

The first parameter is a prefix string: if provided, only pages with names that start with the prefix are included in the resulting list. If this parameter is omitted, all pages are included in the list.

The second parameter is the maximum number of pages to include in the list.

The group parameter determines how the list is presented:

The pages are presented in bulleted lists that are grouped by date (default).
The pages are presented in a single bulleted list.

Tip: if you only want to specify a maximum number of entries and don't want to filter by prefix, specify an empty first parameter, e.g. [[RecentChanges(,10,group=none)]].


Lists all topics, that have been recently active, grouping them by the day they were lastly active. Accepts two parameters: First one is a forum ID. If provided, only topics in that forum are included in the resulting list. Otherwise topics from all forums are listed. Second parameter is a number. I. e. specifying 5 will result in only the five most recently active topics to be included in the list.


This Trac plug-in implements a server sided redirect functionality. The user interface is the wiki macro Redirect (alternatively redirect).



This plug-in allow to place a redirect macro at the start of any wiki page which will cause an server side redirect when the wiki page is viewed.

This plug-in is compatible (i.e. can be used) with the client side redirect macro TracRedirect but doesn't depend on it. Because the redirect is caused by the server (using a HTTP redirect request to the browser) it is much faster and less noticeable for the user. The back-link feature of TracRedirect can also be used for server side redirected pages because both generate the same URL attributes.

To edit a redirecting wiki page access its URL with ?action=edit appended. To view the page either use ?action=view, which will print the redirect target (if TracRedirect isn't active, which will redirect the wiki using client side code), or ?redirect=no which disables redirection of both the ServerSideRedirectPlugin and TracRedirect plug-in.

Direct after the redirect target is added (or modified) Trac will automatically reload it, as it does with all wiki pages. This plug-in will detect this and not redirect but display the wiki page with the redirect target URL printed to provide feedback about the successful change. However, further visits will trigger the redirect.

Usage Examples

The following 'macro' at the begin of the wiki page will cause a redirect to the OtherWikiPage.


Any other TracLink can be used:



Display the list of available repositories.

Can be given the following named arguments:

Select the rendering format:
  • compact produces a comma-separated list of repository prefix names (default)
  • list produces a description list of repository prefix names
  • table produces a table view, similar to the one visible in the Browse View page
Do a glob-style filtering on the repository names (defaults to '*')
Order repositories by the given column (one of "name", "date" or "author")
When set to 1, order by descending order

(since 0.12)


Display a list of all installed notification subscribers, including documentation if available.

Optionally, the name of a specific subscriber can be provided as an argument. In that case, only the documentation for that subscriber will be rendered.

Note that this macro will not be able to display the documentation of subscribers if the PythonOptimize option is enabled for mod_python!


Generate a table of contents for the current page or a set of pages.

If no arguments are given, a table of contents is generated for the current page, with the top-level title stripped:


To generate a table of contents for a set of pages, simply pass them as comma separated arguments to the TOC macro, e.g. as in

[[TOC(TracGuide, TracInstall, TracUpgrade, TracIni, TracAdmin, TracBackup,
      TracLogging, TracPermissions, TracWiki, WikiFormatting, TracBrowser,
      TracRoadmap, TracChangeset, TracTickets, TracReports, TracQuery,
      TracTimeline, TracRss, TracNotification)]]

A wildcard * can be used to fetch a sorted list of all pages starting with the preceding pagename stub:

[[TOC(Trac*, WikiFormatting, WikiMacros)]]

The following control arguments change the default behaviour of the TOC macro:

Argument Description
heading=<x> Override the default heading of "Table of Contents"
noheading Suppress display of the heading.
depth=<n> Display headings of subsequent pages to a maximum depth of <n>.
inline Display TOC inline rather than as a side-bar.
sectionindex Only display the page name and title of each page in the wiki section.
titleindex Only display the page name and title of each page, similar to TitleIndex.
notitle Supress display of page title.
reverse Display TOC sorted in reversed order. (Since
from=page Obtain the list of pages to show from the content (one page name per line) of another wiki page.

For titleindex argument, an empty pagelist will evaluate to all pages:

[[TOC(titleindex, notitle, heading=All pages)]]

The sectionindex argument allows a title index to be generated for all pages in a given section of the wiki. A section is defined by wiki page name, using / as a section level delimiter (like directories in a file system). Giving / or * as the page name produces the same result as titleindex (title of all pages). If a page name ends with a /, only children of this page will be processed. Otherwise, the page given in the argument is also included, if it exists. For sectionindex argument, an empty pagelist will evaluate to all page below the same parent as the current page:

[[TOC(sectionindex, notitle, heading=This section pages)]]

The 'from' option allows you to read the lines of content from another wiki page and use that as the pagelist for the table of contents. The page names listed there are processed as if they are named in the TOC macro (start a line with a # to treat it as a comment). If the wiki page TOC/Guide contains


then these two calls to TOC are equivalent:

[[TOC(TracGuide, TracInstall, TracReports/Active)]]

However, updating page TOC/Guide changes the TOC in all places that use from= to refer to it. This can be useful instead of custom macros like [[TracGuideToc]].


Wiki macro listing tickets that match certain criteria.

This macro accepts a comma-separated list of keyed parameters, in the form "key=value".

If the key is the name of a field, the value must use the syntax of a filter specifier as defined in TracQuery#QueryLanguage. Note that this is not the same as the simplified URL syntax used for query: links starting with a ? character. Commas (,) can be included in field values by escaping them with a backslash (\).

Groups of field constraints to be OR-ed together can be separated by a literal or argument.

In addition to filters, several other named parameters can be used to control how the results are presented. All of them are optional.

The format parameter determines how the list of tickets is presented:

  • list -- the default presentation is to list the ticket ID next to the summary, with each ticket on a separate line.
  • compact -- the tickets are presented as a comma-separated list of ticket IDs.
  • count -- only the count of matching tickets is displayed
  • rawcount -- only the count of matching tickets is displayed, not even with a link to the corresponding query (since 1.1.1)
  • table -- a view similar to the custom query view (but without the controls)
  • progress -- a view similar to the milestone progress bars

The max parameter can be used to limit the number of tickets shown (defaults to 0, i.e. no maximum).

The order parameter sets the field used for ordering tickets (defaults to id).

The desc parameter indicates whether the order of the tickets should be reversed (defaults to false).

The group parameter sets the field used for grouping tickets (defaults to not being set).

The groupdesc parameter indicates whether the natural display order of the groups should be reversed (defaults to false).

The verbose parameter can be set to a true value in order to get the description for the listed tickets. For table format only. deprecated in favor of the rows parameter

The rows parameter can be used to specify which field(s) should be viewed as a row, e.g. rows=description|summary

The col parameter can be used to specify which fields should be viewed as columns. For table format only.

For compatibility with Trac 0.10, if there's a last positional parameter given to the macro, it will be used to specify the format. Also, using "&" as a field separator still works (except for order) but is deprecated.


Insert an alphabetic list of all wiki pages into the output.

Accepts a prefix string as parameter: if provided, only pages with names that start with the prefix are included in the resulting list. If this parameter is omitted, all pages are listed. If the prefix is specified, a second argument of value hideprefix can be given as well, in order to remove that prefix from the output.

The prefix string supports the standard relative-path notation when using the macro in a wiki page. A prefix string starting with ./ will be relative to the current page, and parent pages can be specified using ../.

Several named parameters can be specified:

  • format=compact: The pages are displayed as comma-separated links.
  • format=group: The list of pages will be structured in groups according to common prefix. This format also supports a min=n argument, where n is the minimal number of pages for a group.
  • format=hierarchy: The list of pages will be structured according to the page name path hierarchy. This format also supports a min=n argument, where higher n flatten the display hierarchy
  • depth=n: limit the depth of the pages to list. If set to 0, only toplevel pages will be shown, if set to 1, only immediate children pages will be shown, etc. If not set, or set to -1, all pages in the hierarchy will be shown.
  • include=page1:page*2: include only pages that match an item in the colon-separated list of pages. If the list is empty, or if no include argument is given, include all pages.
  • exclude=page1:page*2: exclude pages that match an item in the colon- separated list of pages.

The include and exclude lists accept shell-style patterns.


Display help for trac-admin commands.


[[TracAdminHelp]]               # all commands
[[TracAdminHelp(wiki)]]         # all wiki commands
[[TracAdminHelp(wiki export)]]  # the "wiki export" command
[[TracAdminHelp(upgrade)]]      # the upgrade command


Display a table of content for the Trac guide.

This macro shows a quick and dirty way to make a table-of-contents for the Help/Guide. The table of contents will contain the Trac* and WikiFormatting pages, and can't be customized. See the TocMacro for a more customizable table of contents.


Produce documentation for the Trac configuration file.

Typically, this will be used in the TracIni page. The macro accepts two ordered arguments and two named arguments.

The ordered arguments are a configuration section filter, and a configuration option name filter: only the configuration options whose section and name start with the filters are output.

The named arguments can be specified:

a glob-style filtering on the section names
a glob-style filtering on the option names


TracNav: The Navigation Bar for Trac

This macro implements a fully customizable navigation bar for the Trac wiki engine. The contents of the navigation bar is a wiki page itself and can be edited like any other wiki page through the web interface. The navigation bar supports hierarchical ordering of topics. The design of TracNav mimics the design of the TracGuideToc that was originally supplied with Trac. The drawback of TracGuideToc is that it is not customizable without editing its source code and that it does not support hierarchical ordering.




To use TracNav, create an index page for your site and call the TracNav macro on each page, where the navigation bar should be displayed. The index page is a regular wiki page. The page with the table of contents must include an unordered list of links that should be displayed in the navigation bar.

To display the navigation bar on a page, you must call the TracNav macro on that page an pass the name of your table of contents as argument.

Additional information and a life example

Please visit:

Author and License

  • Copyright 2005-2006, Bernhard Haumacher (haui at
  • Copyright 2005-2010, Thomas Moschny (thomas.moschny at
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA


Displays content of a discussion topic. Unless argument passed, it tries to find the topic with the same name as the current wiki page. If a name is passed, displays that topic.


Render a workflow graph.

This macro accepts a TracWorkflow configuration and renders the states and transitions as a directed graph. If no parameters are given, the current ticket workflow is rendered. In WikiProcessors mode the width and height arguments can be specified.

(Defaults: width = 800 and height = 600)



    [[Workflow(go = here -> there; return = there -> here)]]

    #!Workflow width=700 height=700
    leave = * -> *
    leave.operations = leave_status
    leave.default = 1

    create = <none> -> new
    create.default = 1

    create_and_assign = <none> -> assigned
    create_and_assign.label = assign
    create_and_assign.permissions = TICKET_MODIFY
    create_and_assign.operations = may_set_owner

    accept = new,assigned,accepted,reopened -> accepted
    accept.permissions = TICKET_MODIFY
    accept.operations = set_owner_to_self

    resolve = new,assigned,accepted,reopened -> closed
    resolve.permissions = TICKET_MODIFY
    resolve.operations = set_resolution

    reassign = new,assigned,accepted,reopened -> assigned
    reassign.permissions = TICKET_MODIFY
    reassign.operations = set_owner

    reopen = closed -> reopened
    reopen.permissions = TICKET_CREATE
    reopen.operations = del_resolution


See macro Redirect.

Contributed macros

The Trac Hacks site provides a large collection of macros and other Trac plugins contributed by the Trac community. If you are looking for new macros, or have written one that you would like to share, please visit that site.

Developing Custom Macros

Macros, like Trac itself, are written in the Python programming language and are a type of plugin.

Here are 2 simple examples showing how to create a Macro. For more information about developing macros, see the development resources and sample-plugins.

Macro without arguments

To test the following code, copy it to in the TracEnvironment's plugins/ directory.

from trac.util.datefmt import datetime_now, format_datetime, utc
from trac.util.html import tag
from import WikiMacroBase

class TimestampMacro(WikiMacroBase):
    _description = "Inserts the current time (in seconds) into the wiki page."

    def expand_macro(self, formatter, name, content, args=None):
        t = datetime_now(utc)
        return tag.strong(format_datetime(t, '%c'))

Macro with arguments

To test the following code, copy it to in the TracEnvironment's plugins/ directory.

from trac.util.translation import cleandoc_
from import WikiMacroBase

class HelloWorldMacro(WikiMacroBase):
    _description = cleandoc_(
    """Simple HelloWorld macro.

    Note that the name of the class is meaningful:
     - it must end with "Macro"
     - what comes before "Macro" ends up being the macro name

    The documentation of the class (i.e. what you're reading)
    will become the documentation of the macro, as shown by
    the !MacroList macro (usually used in the WikiMacros page).

    def expand_macro(self, formatter, name, content, args=None):
        """Return some output that will be displayed in the Wiki content.

        `name` is the actual name of the macro (no surprise, here it'll be
        `content` is the text enclosed in parenthesis at the call of the
          macro. Note that if there are ''no'' parenthesis (like in, e.g.
          [[HelloWorld]]), then `content` is `None`.
        `args` will contain a dictionary of arguments when called using the
          Wiki processor syntax and will be `None` if called using the
          macro syntax.
        return 'Hello World, content = ' + unicode(content)

Note that expand_macro optionally takes a 4th parameter args. When the macro is called as a WikiProcessor, it is also possible to pass key=value processor parameters. If given, those are stored in a dictionary and passed in this extra args parameter. When called as a macro, args is None.

For example, when writing:

{{{#!HelloWorld style="polite" -silent verbose
<Hello World!>

<Hello World!>

[[HelloWorld(<Hello World!>)]]

One should get:

Hello World, text = <Hello World!>, args = {'style': u'polite', 'silent': False, 'verbose': True}
Hello World, text = <Hello World!>, args = {}
Hello World, text = <Hello World!>, args = None

Note that the return value of expand_macro is not HTML escaped. Depending on the expected result, you should escape it yourself (using return Markup.escape(result)), or if this is indeed HTML, wrap it in a Markup object: return Markup(result) (from trac.util.html import Markup).

You can also recursively use a wiki formatter to process the content as wiki markup:

from import format_to_html
from import WikiMacroBase

class HelloWorldMacro(WikiMacroBase):
    def expand_macro(self, formatter, name, content, args):
        content = "any '''wiki''' markup you want, even containing other macros"
        # Convert Wiki markup to HTML
        return format_to_html(self.env, formatter.context, content)