1
2class LookupDictionary(dict):
3    """
4    a dictionary which can lookup value by key, or keys by value
5    """
6    def __init__(self, items=[]):
7        """items can be a list of pair_lists or a dictionary"""
8        dict.__init__(self, items)
9
10    def get_keys_for_value(self, value, fail_value = None):
11        """find the key(s) as a list given a value"""
12        list_result = [item[0] for item in self.items() if item[1] == value]
13        if len(list_result) > 0:
14            return list_result
15        return fail_value
16
17    def get_first_key_for_value(self, value, fail_value = None):
18        """return the first key of this dictionary given the value"""
19        list_result = [item[0] for item in self.items() if item[1] == value]
20        if len(list_result) > 0:
21            return list_result[0]
22        return fail_value
23
24    def get_value(self, key, fail_value = None):
25        """find the value given a key"""
26        if key in self:
27            return self[key]
28        return fail_value
29
30
31class Enum(LookupDictionary):
32
33    def __init__(self, initial_value=0, items=[]):
34        """items can be a list of pair_lists or a dictionary"""
35        LookupDictionary.__init__(self, items)
36        self.value = initial_value
37
38    def set_value(self, v):
39        v_typename = typeof(v).__name__
40        if v_typename == 'str':
41            if str in self:
42                v = self[v]
43            else:
44                v = 0
45        else:
46            self.value = v
47
48    def get_enum_value(self):
49        return self.value
50
51    def get_enum_name(self):
52        return self.__str__()
53
54    def __str__(self):
55        s = self.get_first_key_for_value (self.value, None)
56        if s == None:
57            s = "%#8.8x" % self.value
58        return s
59
60    def __repr__(self):
61        return self.__str__()