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#format wiki
#language en

<<Include(A:style)>>

== Create a custom filter ==
=== Objective ===
This page shows you how to create a custom filter. For that, we are going to write a python script, and add it as an extension.

Our filter will convert the text passed to it to uppercase.

==== Write script ====
First step, write the script and save it somewhere.

{{{#!python
from mercurial import templatefilters

def upper(s):
    return s.upper()

def extsetup(ui):
    templatefilters.filters["upper"] = upper
}}}
==== Add Extension ====
In mercurial.ini, add this script under the [extensions] section.

{{{
[extensions]
upper = ~/.hgext/myfeature.py
}}}
(if this doesn't work, see [[UsingExtensions|Using Mercurial Extensions]] for help on configuring extensions)

=== Example ===
{{{
>hg tip --template "{author|upper}\n"
GUIDO VAN ROSSUM <BDFL@PYTHON.ORG>
}}}
----
CategoryDeveloper