deb-python-multi-key-dict/README.txt
2014-11-22 22:18:00 +00:00

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multi_key_dict
======================
Implementation of a multi-key dictionary, i.e.:
(key1[,key2, ..]) => value
This dictionary has a similar interface to the standard dictionary => but is extended to support multiple keys referring to the same element.
If element is created using multiple keys, e.g.:
.. code:: python
from multi_key_dict import multi_key_dict
k = multi_key_dict()
k[1000, 'kilo', 'k'] = 'kilo (x1000)'
print k[1000] # will print 'kilo (x1000)'
print k['k'] # will also print 'kilo (x1000)'
# the same way objects can be updated, deleted:
# and if an object is updated using one key, the new value will
# be accessible using any other key, e.g. for example above:
k['kilo'] = 'kilo'
print k[1000] # will now print 'kilo' as value was updated
These elements can be accessed using either of those keys (e.g for read/update/deletion).
Multi-key dict provides also extended interface for iterating over items and keys (e.g. by the key type), which might be useful when creating, e.g. dictionaries with index-name key pair allowing to iterate over items using either: names or indexes.
It can be useful for many many other similar use-cases, and there is no limit to the number of keys used to map to the value.
There are few other useful methods, e.g. to iterate over dictionary (by/using) selected key type, finding other keys mapping to the same value etc. Refer to example/test code to see it in action.