Use source reST role instead of file where it makes sense.
source generates a nifty link to the Mercurial web viewer.
diff --git a/Doc/howto/regex.rst b/Doc/howto/regex.rst
index 07a8b56..3ac03ca 100644
--- a/Doc/howto/regex.rst
+++ b/Doc/howto/regex.rst
@@ -360,7 +360,7 @@
You can learn about this by interactively experimenting with the :mod:`re`
module. If you have :mod:`tkinter` available, you may also want to look at
-:file:`Tools/demo/redemo.py`, a demonstration program included with the
+:source:`Tools/demo/redemo.py`, a demonstration program included with the
Python distribution. It allows you to enter REs and strings, and displays
whether the RE matches or fails. :file:`redemo.py` can be quite useful when
trying to debug a complicated RE. Phil Schwartz's `Kodos
@@ -495,7 +495,7 @@
the same ones in several locations, then it might be worthwhile to collect all
the definitions in one place, in a section of code that compiles all the REs
ahead of time. To take an example from the standard library, here's an extract
-from the now deprecated :file:`xmllib.py`::
+from the now-defunct Python 2 standard :mod:`xmllib` module::
ref = re.compile( ... )
entityref = re.compile( ... )