diff -r 4d7bf6bdcd8f -r 8f23804302d0 app/soc/logic/key_name.py
--- a/app/soc/logic/key_name.py	Wed Oct 01 20:48:58 2008 +0000
+++ b/app/soc/logic/key_name.py	Wed Oct 01 20:52:39 2008 +0000
@@ -23,27 +23,7 @@
   ]
 
 
-# start with ASCII digit or lowercase
-#   (additional ASCII digit or lowercase
-#     -OR-
-#   underscore and ASCII digit or lowercase)
-#     zero or more of OR group
-LINKNAME_PATTERN_CORE = r'[0-9a-z](?:[0-9a-z]|_[0-9a-z])*'
-
-LINKNAME_PATTERN = r'^%s$' % LINKNAME_PATTERN_CORE
-LINKNAME_ARG_PATTERN = r'(?P<linkname>%s)' % LINKNAME_PATTERN_CORE
-
-
-# partial path is multiple linkname chunks,
-#   each separated by a trailing /
-#     (at least 1)
-# followed by a single linkname with no trailing /
-WORK_PATH_LINKNAME_ARGS_PATTERN = (
-    r'(?P<partial_path>%(linkname)s(?:/%(linkname)s)*)/'
-     '(?P<linkname>%(linkname)s)' % {
-        'linkname': LINKNAME_PATTERN_CORE})
-
-WORK_PATH_LINKNAME_PATTERN = r'^%s$' % WORK_PATH_LINKNAME_ARGS_PATTERN
+from soc.logic import path_linkname
 
 
 class Error(Exception):
@@ -56,45 +36,6 @@
   return '%s.%s' % (cls.__module__, cls.__name__) 
 
 
-def combinePath(path_parts):
-  """Returns path components combined into a single string.
-  
-  Args:
-    path_parts: a single path string, or a list of path part strings,
-      or a nested list of path part strings (where the zeroeth element in
-      the list is itself a list); for example:
-        'a/complete/path/in/one/string'
-        ['some', 'path', 'parts']
-        [['path', 'parts', 'and', 'a'], 'link name']
-
-  Returns:
-    None if path_parts is False (None, empty string, etc.) or if
-    any list elements are False (an empty list, empty string, etc.);
-    otherwise, the combined string with the necessary separators.
-  """
-  if not path_parts:
-    # completely empty input, so return early
-    return None
-
-  if not isinstance(path_parts, (list, tuple)):
-    # a single path string, so just return it as-is (nothing to do)
-    return path_parts
-  
-  flattened_parts = []
-  
-  for part in path_parts:
-    if not part:
-      # encountered a "False" element, which invalidates everything else
-      return None    
-  
-    if isinstance(part, (list, tuple)):
-      flattened_parts.extend(part)
-    else:
-      flattened_parts.append(part)
-
-  return '/'.join(flattened_parts)
-
-
 def nameDocument(partial_path, link_name=None):
   """Returns a Document key name constructed from a path and link name.
     
@@ -114,7 +55,7 @@
   if link_name:
     path.append(link_name)
 
-  path = combinePath(path)
+  path = path_linkname.combinePath(path)
 
   if not path:
     raise Error('"path" must be non-False: "%s"' % path)
@@ -170,7 +111,7 @@
     Error if sponsor_ln, program_ln, and link_Name combine to produce
     a "False" path (None, empty string, etc.)
   """
-  path = combinePath([[sponsor_ln, program_ln], link_name])
+  path = path_linkname.combinePath([[sponsor_ln, program_ln], link_name])
   
   if not path:
     raise Error('"path" must be non-False: "%s"' % path)
@@ -190,7 +131,7 @@
     Error if sponsor_ln, program_ln, and link_Name combine to produce
     a "False" path (None, empty string, etc.)
   """
-  path = combinePath([[sponsor_ln, program_ln], link_name])
+  path = path_linkname.combinePath([[sponsor_ln, program_ln], link_name])
   
   if not path:
     raise Error('"path" must be non-False: "%s"' % path)