Patch to make errors in templates not cause the thing to die, but to send
*something* so that you can diagnose the problem more easily.
from mailman-developers, 2 September 1999.


diff -c -r1.75 Utils.py
*** Utils.py    1999/09/02 19:39:08     1.75
--- Utils.py    1999/09/02 19:51:38
***************
*** 27,32 ****
--- 27,34 ----
  import os
  import string
  import re
+ from UserDict import UserDict
+ from types import StringType
  # XXX: obsolete, should use re module
  import regsub
  import random
***************
*** 620,625 ****
--- 622,645 ----
  
  
  
+ class SafeDict(UserDict):
+     """Dictionary which returns a default value for unknown keys.
+ 
+     This is used in maketext so that editing templates is a bit more robust.
+     """
+     def __init__(self, d):
+         UserDict.__init__(self)
+         self.update(d)
+ 
+     def __getitem__(self, key):
+         try:
+             return self.data[key]
+         except KeyError:
+             if type(key) == StringType:
+                 return '%('+key+')s'
+             else:
+                 return '<Missing key: %s>' % `key`
+ 
+ 
  def maketext(templatefile, dict, raw=0):
      """Make some text from a template file.
  
***************
*** 631,639 ****
      fp = open(file)
      template = fp.read()
      fp.close()
      if raw:
!         return template % dict
!     return wrap(template % dict)
  
  
  
--- 651,660 ----
      fp = open(file)
      template = fp.read()
      fp.close()
+     text = template % SafeDict(dict)
      if raw:
!         return text
!     return wrap(text)