choice_enum

Wrapper class for defining DRY, encapsulated choice options for CharFields.

ChoiceEnumeration

ChoiceEnumeration class can be declared at the module or class level in the following format:

class ChoiceClass(ChoiceEnumeration):
    ATTR1 = ChoiceEnumeration.Option('db_value1', 'Human readable text 1')
    ATTR2 = ChoiceEnumeration.Option('db_value2', 'Human readable text 2')

The following attributes are generated on the ChoiceEnumeration child class:

• ALL_OPTIONS - a tuple of the supplied options
• CHOICES - a Django char field choices-compatible tuple
• CHOICES_DICT - a dictionary of option:text values
• DEFAULT - (optional) the item marked as default

A typical Django example would look like:

class SomeModel(models.Model):
    class MetaVar(ChoiceEnumeration):
        FOO  = ChoiceEnumeration.Option('foo',  'Foo Choice', default=True)
        BAR  = ChoiceEnumeration.Option('bar',  'Bar Option')
        BAZ  = ChoiceEnumeration.Option('baz',  'Baz Pick')
        SPAM = ChoiceEnumeration.Option('spam', 'Spam spam spam')
        EGGS = ChoiceEnumeration.Option('eggs', 'Eggs, Spam, and Ham')

Example interactive usage::

>>> class MetaVar(ChoiceEnumeration):
...     FOO  = ChoiceEnumeration.Option('foo',  'Foo Choice', default=True)
...     BAR  = ChoiceEnumeration.Option('bar',  'Bar Option')
...     BAZ  = ChoiceEnumeration.Option('baz',  'Baz Pick')
...     SPAM = ChoiceEnumeration.Option('spam', 'Spam spam spam')
...     EGGS = ChoiceEnumeration.Option('eggs', 'Eggs, Spam, and Ham')
>>> MetaVar.FOO
u'foo'
>>> MetaVar.ALL_OPTIONS
(u'foo', u'bar', u'baz', u'spam', u'eggs')
>>> MetaVar.CHOICES
((u'foo', 'Foo Choice'), (u'bar', 'Bar Option'), (u'baz', 'Baz Pick'), (u'spam', 'Spam spam spam'), (u'eggs', 'Eggs, Spam, and Ham'))
>>> MetaVar.CHOICES_DICT
{u'baz': 'Baz Pick', u'eggs': 'Eggs, Spam, and Ham', u'foo': 'Foo Choice', u'bar': 'Bar Option', u'spam': 'Spam spam spam'}
>>> MetaVar.DEFAULT
u'foo'
>>> MetaVar.CHOICES_DICT[MetaVar.FOO]
'Foo Choice'

make_enum_class

make_enum_class dynamically generates a ChoiceEnumeration derived class.

Example:

from choice_enum import make_enum_class, Option
MetaVar = make_enum_class('MetaVar',
    FOO=Option('foo',  'Foo Choice', default=True),
    BAR=Option('bar',  'Bar Option'),
    BAZ=Option('baz',  'Baz Pick')
)