imported patch containers-overlay-in-progress

--HG--
branch : feature-containers

1 files changed, 8 insertions, 3 deletions

diff --git a/urwid/widget.py b/urwid/widget.py
index 6f6e4bb..0e4d01b 100644
--- a/urwid/widget.py
+++ b/urwid/widget.py
@@ -33,18 +33,20 @@ from urwid.command_map import command_map
 from urwid.split_repr import split_repr, remove_defaults, python3_repr
 
 
+# define some names for these constants to avoid misspellings in the source
+# and to document the constant strings we are using
+
 # Widget sizing methods
-# (use the same string objects to make some comparisons faster)
 FLOW = 'flow'
 BOX = 'box'
 FIXED = 'fixed'
 
-# Text alignment modes 
+# Text alignment modes
 LEFT = 'left'
 RIGHT = 'right'
 CENTER = 'center'
 
-# Filler alignment modes 
+# Filler alignment modes
 TOP = 'top'
 MIDDLE = 'middle'
 BOTTOM = 'bottom'
@@ -60,6 +62,9 @@ GIVEN = 'given'
 RELATIVE = 'relative'
 RELATIVE_100 = (RELATIVE, 100)
 
+# extra constants for Pile/Columns
+WEIGHT = 'weight'
+
 
 class WidgetMeta(MetaSuper, signals.MetaSignals):
     """