Filter items in a dict of dict

Here's a way to do it:

adict = {1: {'process':False, 'length':10}, 2: {'process':True, 'length':34}, 3:{'process': False, 'length': -3}}

def somefiltering(filterDict, *criteria):
    return [key for key in filterDict if all(criterion(filterDict[key]) for criterion in criteria)]

Note that your somefiltering function will need to have the dictionary as an argument.

Example usage:

somefiltering(adict, lambda d:d['process'], lambda d:d['length']>5)
# Result: [2]

somefiltering(adict, lambda d:d['length'] < 20)
# Result: [1, 3]

somefiltering(adict, lambda d:d['process'], lambda d:d['length']<5)
# Result: []

If you need list of keys, it's gonna be

[k for k,v in adict.items() if creterion(v)]

And use dict.iteritems() for 2.x.

Given a list of callables named criteria, the following filter expression will list only the dict keys whose corresponding values meet all the criteria.

filter(lambda key: all(crit(adict[key]) for crit in criteria), adict.keys())