[dbfpy-checkins] dbfpy/dbfpy utils.py,1.3,1.4

[alexander s. <a1...@us...>]

Update of /cvsroot/dbfpy/dbfpy/dbfpy
In directory sc8-pr-cvs12.sourceforge.net:/tmp/cvs-serv8683

Modified Files:
	utils.py 
Log Message:
added INVALID_VALUE

Index: utils.py
===================================================================
RCS file: /cvsroot/dbfpy/dbfpy/dbfpy/utils.py,v
retrieving revision 1.3
retrieving revision 1.4
diff -C2 -d -r1.3 -r1.4
*** utils.py	10 Feb 2007 19:00:37 -0000	1.3
--- utils.py	11 Feb 2007 08:57:17 -0000	1.4
***************
*** 5,8 ****
--- 5,9 ----
  """
  """History (most recent first):
+ 11-feb-2007 [als]   added INVALID_VALUE
  10-feb-2007 [als]   allow date strings padded with spaces instead of zeroes
  20-dec-2005 [yc]    handle long objects in getDate/getDateTime
***************
*** 125,127 ****
--- 126,170 ----
  
  
+ class _InvalidValue(object):
+ 
+     """Value returned from DBF records when field validation fails
+ 
+     The value is not equal to anything except for itself
+     and equal to all empty values: None, 0, empty string etc.
+     In other words, invalid value is equal to None and not equal
+     to None at the same time.
+ 
+     This value yields zero upon explicit conversion to a number type,
+     empty string for string types, and False for boolean.
+ 
+     """
+ 
+     def __eq__(self, other):
+         return not other
+ 
+     def __ne__(self, other):
+         return not (other is self)
+ 
+     def __nonzero__(self):
+         return False
+ 
+     def __int__(self):
+         return 0
+     __long__ = __int__
+ 
+     def __float__(self):
+         return 0.0
+ 
+     def __str__(self):
+         return ""
+ 
+     def __unicode__(self):
+         return u""
+ 
+     def __repr__(self):
+         return "<INVALID>"
+ 
+ # invalid value is a constant singleton
+ INVALID_VALUE = _InvalidValue()
+ 
  # vim: set et sts=4 sw=4 :