= Python Enum =

'''`enum`''' is a module that provides an enum-like data type.

<<TableOfContents>>

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== Classes ==



=== Enum ===

`enum.Enum` is a basic enum.

{{{
import enum

class Color(enum.Enum):
    RED = 1
    GREEN = 2
    BLUE = 3

# alternatively...
Color = enum.Enum('Color', ['RED', 'GREEN', 'BLUE'])

Color.BLUE.name  #'BLUE'
Color.RED.value  #1
}}}

The `auto` function will set integer values incrementing from 1.

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=== Flag ===

`enum.Flag` is an enum that supports [[Python/Builtins/Operators#Bitwise_Binary|bitwise operations]].  These operations return a `enum.Flag` value.

{{{
import enum

class Color(enum.Flag):
    RED = enum.auto()
    GREEN = enum.auto()
    BLUE = enum.auto()

purple = Color.RED | Color.BLUE
white = Color.RED | Color.GREEN | Color.BLUE

Color.GREEN in purple  #False
Color.GREEN in white   #True
purple in white        #True
white in purple        #False
}}}

The `auto` function will set sequential powers of two starting from 1.

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=== IntEnum ===

`enum.IntEnum` is the same as `enum.Enum` but the values are always [[Python/Builtins/Types#Int|integers]].

The `auto` function will set integer values incrementing from 1.

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=== IntFlag ===

`enum.IntFlag` is the same as `enum.Flag` but the values can also behave like [[Python/Builtins/Types#Int|integers]]. If an integer operation is performed, an integer is returned.

If a bitwise operation is performed, the result may or may not be a `enum.Flag`.

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=== ReprEnum ===

`enum.ReprEnum` is the same as `enum.Enum` except that calling `str()` is passed through. This can be useful for creating subclasses of `enum.Enum`.

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=== StrEnum ===

`enum.StrEnum` is the same as `enum.Enum` but the values are always [[Python/Builtins/Types#Str|strings]].

The `auto` function will set a value of the member's name pushed to lowercase.

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== Meta Classes ==



=== EnumType ===

`enum.EnumType` is the metaclass for all other enum-like classes.

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== Functions ==



=== Auto ===

Instead of providing a value to an enum member, the `auto` function can be provided. It causes incrementing values to be set for the members.

{{{
import enum

class People(enum.Enum):
    Me = enum.auto()
    You = enum.auto()
}}}

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== Decorators ==



=== @Unique ===

If a `enum.Enum` (or subclass) is decorated with `@unique`, the members are inspected for duplicated values. A `ValueError` will be raised at runtime.

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=== @Verify ===

If a `enum.Enum` (or subclass) is decorated with `@verify`, the members are inspected for some behavior. See the constants below for options.

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== Constants ==

Fittingly, the constants of `enum` are stored in enums.

These constants are used for `verify`.

||'''Constants'''||'''Meaning'''||
||`CONTINUOUS`   || ||
||`NAMED_FLAGS`  || ||
||`UNIQUE`       || ||

These constants are used for configuring `enum.IntFlag` behavior.

||'''Constants'''||'''Meaning'''||
||`CONFIRM`|| ||
||`EJECT`  || ||
||`KEEP`   || ||
||`STRICT` || ||

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== See also ==

[[https://docs.python.org/3/library/enum.html|Python enum module documentation]]

[[https://pymotw.com/3/enum/|Python Module of the Day article for enum]]



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