[ANN] aenum 1.3.0 released

Ethan Furman ethan at stoneleaf.us
Sun Mar 13 04:20:41 EDT 2016

I am thrilled to announce the release of

   aenum 1.3.0

aenum --- advanced enumerations, named tuples, and named constants

aenum includes the new Python stdlib enum module available in Python 3.4
backported for previous versions of Python from 2.7 and 3.3+
tested on 2.7, and 3.3+

An ``Enum`` is a set of symbolic names (members) bound to unique, 
constant values.  Within an enumeration, the members can be compared by 
identity, and the enumeration itself can be iterated over.

A ``NamedTuple`` is a class-based, fixed-length tuple with a name for 
each possible position accessible using attribute-access notation.

A ``Constant`` is a class of named values whose members cannot be 
rebound;  it lacks all other ``Enum`` capabilities, however; 
consequently, it can have duplicate values.  There is also a ``module`` 
function that can insert the ``Constant`` class into ``sys.modules`` 
where it will appear to be a module whose top-level names cannot be rebound.

Module Contents

    Base class for ``creating NamedTuples``, either by subclassing or 
via it's functional API.

    Constant class for creating groups of constants.  These names cannot
    be rebound to other values.

    Base class for creating enumerated constants.

    Base class for creating enumerated constants that are also
    subclasses of ``int``.

    Derived class that automatically assigns an ``int`` value to each

    Derived class that adds ``<``, ``<=``, ``>=``, and ``>`` methods to
    an ``Enum``.

    Derived class that ensures only one name is bound to any one value.

    Enum class decorator that ensures only one name is bound to any one

    Descriptor to add constant values to an ``Enum``

    Helper to transform target global variables into an ``Enum``.

    Helper for specifying keyword arguments when creating ``Enum``

    Helper for inserting ``Enum`` members into a namespace (usually

    Helper for adding new ``Enum`` members after creation.

    Function to take a ``Constant`` or ``Enum`` class and insert it into
    ``sys.modules`` with the affect of a module whose top-level constant
    and member names cannot be rebound.

    Descriptor to add a normal (non-``Enum`` member) attribute to an
    ``Enum`` or ``Constant``.

Creating an Enum

Enumerations can be created using the ``class`` syntax, which makes them
easy to read and write.  To define an enumeration, subclass ``Enum`` as

     >>> from aenum import Enum
     >>> class Color(Enum):
     ...     red = 1
     ...     green = 2
     ...     blue = 3

The ``Enum`` class is also callable, providing the following functional 

     >>> Animal = Enum('Animal', 'ant bee cat dog')
     >>> Animal
     <enum 'Animal'>
     >>> Animal.ant
     <Animal.ant: 1>
     >>> Animal.ant.value
     >>> list(Animal)
     [<Animal.ant: 1>, <Animal.bee: 2>, <Animal.cat: 3>, <Animal.dog: 4>]

Creating NamedTuples


The most common way to create a new NamedTuple will be via the 
functional API::

     >>> from aenum import NamedTuple
     >>> Book = NamedTuple('Book', 'title author genre', module=__name__)


The simple method of creating ``NamedTuples`` requires always specifying 
all possible arguments when creating instances; failure to do so will 
raise exceptions.

However, it is possible to specify both docstrings and default values 
when creating a ``NamedTuple`` using the class method::

     >>> class Point(NamedTuple):
     ...     x = 0, 'horizontal coordinate', 0
     ...     y = 1, 'vertical coordinate', 0
     >>> Point()
     Point(x=0, y=0)

Creating Constants

``Constant`` is similar to ``Enum``, but do not support the ``Enum``
protocols, and have no restrictions on duplications::

     >>> class K(Constant):
     ...     PI = 3.141596
     ...     TAU = 2 * PI
     >>> K.TAU


Some of the inspirations:

An Enum of Enums:  http://stackoverflow.com/q/30471864/208880

C-like Enums:      http://stackoverflow.com/q/29264941/208880

Extending Enums:   http://stackoverflow.com/q/28126314/208880

Named constants:   http://stackoverflow.com/q/31537316/208880

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