'''Beware: I'm by no means an expert and just quickly collected Information that seems right. The sources for these Macros are at: ticket:5274'''

 * ticket:5274/HelloWorld.py
 * ticket:5274/Timestamp.py

= Implementation Changes =

[wiki:Trac0.11 Trac0.11] has significant changes for it's Macro processing and Implementation.

Here are 2 simple examples on how to create a Macro with [wiki:Trac0.11 Trac0.11] have a look at source:trunk/sample-plugins/Timestamp.py for an example that shows the difference between old style and new style macros and also source:trunk/wiki-macros/README which Provides a little more insight.

== Macro without arguments ==
It should be saved as `TimeStamp.py` as Trac will use the module name as the Macro name
{{{
from trac.core import *
from trac.wiki.macros import WikiMacroBase
from StringIO import StringIO
import time

__all__ = ['TimestampMacro']

class TimestampMacro(WikiMacroBase):
        """
        Macro for inserting timestamp

        {{{
        [[Timestamp]]
        }}}
        """
        def expand_macro(self, formatter, name, args):
                buf = StringIO()
                t = time.localtime()
                buf = "<b>%s</b>" % time.strftime('%c', t)
                return buf
}}}

== Macro with arguments ==
It should be saved as `HelloWorld.py` as Trac will use the module name as the Macro name
{{{
"""Example macro."""
from trac.core import *
from trac.wiki.macros import WikiMacroBase
from trac.util import escape

__all__ = ['HelloWorldMacro']

class HelloWorldMacro(WikiMacroBase):
        """
        Demo macro for a greeting with an argument.

        {{{
        [[HelloWorld(args)]]
        }}}

        """
        def expand_macro(self, formatter, name, args):
                # args will be `None` if the macro is called without parenthesis.
                txt = args or 'No arguments'

                # then, as `txt` comes from the user, it's important to guard against
                # the possibility to inject malicious HTML/Javascript, by using `escape()`:
                return 'Hello World, args = ' + escape(txt)
}}}