Kenneth at 17:21, 17 September 2025

2025-09-17T17:21:31Z

← Older revision		Revision as of 17:21, 17 September 2025
Line 29:		Line 29:
	try:		try:
	return return Color[color_name_str]		return return Color[color_name_str]
	except ~~ValueError~~:		except KeyError:
	return None		return None
	</pre>		</pre>

Kenneth: Created page with "== enum — Support for enumerations == Python 3: enum — Support for enumerations https://docs.python.org/3/library/enum.html

 from enum import Enum  # class syntax class Color(Enum):     RED = 1     GREEN = 2     BLUE = 3  # functional syntax Color = Enum('Color', ['RED', 'GREEN', 'BLUE'])

Convert string name or value to enum:

 def value_to_enum(color_value_str):     try:         return Color(color_value_str)     except ValueError:         retu..."

2025-09-16T19:58:40Z

Created page with "== enum — Support for enumerations == Python 3: enum — Support for enumerations https://docs.python.org/3/library/enum.html <pre> from enum import Enum # class syntax class Color(Enum): RED = 1 GREEN = 2 BLUE = 3 # functional syntax Color = Enum('Color', ['RED', 'GREEN', 'BLUE']) </pre> Convert string name or value to enum: <pre> def value_to_enum(color_value_str): try: return Color(color_value_str) except ValueError: retu..."

New page

== enum — Support for enumerations ==

Python 3:
enum — Support for enumerations
https://docs.python.org/3/library/enum.html

<pre>
from enum import Enum

# class syntax
class Color(Enum):
RED = 1
GREEN = 2
BLUE = 3

# functional syntax
Color = Enum('Color', ['RED', 'GREEN', 'BLUE'])
</pre>

Convert string name or value to enum:
<pre>
def value_to_enum(color_value_str):
try:
return Color(color_value_str)
except ValueError:
return None

def name_to_enum(color_name_str):
try:
return return Color[color_name_str]
except ValueError:
return None
</pre>

---

Python 2: [http://stackoverflow.com/questions/36932/how-can-i-represent-an-enum-in-python]
<pre>
class Enum(set):
""" Basic enumerated type

Example
>>> Animals = phi.Enum(["DOG", "CAT", "HORSE"])
>>> Animals.DOG
'DOG'
>>> 'HORSE' in Animals
True
"""
def __getattr__(self, name):
if name in self:
return name
raise AttributeError("Missing Enum property: %s" % name)
def __setattr__(self, name, value): # this makes it read-only
raise AttributeError("Unable to modify Enum property: %s (%s)" % (name, value))

Animals = Enum(["DOG", "CAT", "HORSE"])

print(Animals.DOG) # 'DOG'
</pre>

----------

Alternative:
<pre>
class Stationery:
Pen, Pencil, Eraser = range(0, 3)
</pre>

One liner:
class Enum(tuple): __getattr__ = tuple.index

<pre>
>>> State = Enum(['Unclaimed', 'Claimed'])
>>> State.Claimed
1
>>> State[1]
'Claimed'
>>> State
('Unclaimed', 'Claimed')
>>> range(len(State))
[0, 1]
>>> [(k, State[k]) for k in range(len(State))]
[(0, 'Unclaimed'), (1, 'Claimed')]
>>> [(k, getattr(State, k)) for k in State]
[('Unclaimed', 0), ('Claimed', 1)]
</pre>

Python 3 supports enum natively with the enum.Enum library:

Python/enum - Revision history

Kenneth at 17:21, 17 September 2025