The Order Of Dictionary Entries

I am aware that dictionary order is not guaranteed.  But I ran into
something puzzling today.  I filled a dictionary dynamically as a
program ran.  Up to a certain point, the key order was the order
in which things were added.  However, at some point, the dictionary
appeared to reorder its contents in some non-deterministic way - in
fact, it looked like it was putting all the uppercase keys first,
followed by lowercase keys.

I'm just curious, just what _is_ the approach used for ordering
dictionary keys?

(This was confirmed on both Unix and Win32, BTW).
-- 
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Tim Daneliuk     tundra at tundraware.com
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