Create an enum class from a list of strings in Python

Question

When I run this

from enum import Enum

class MyEnumType(str, Enum):
    RED   = 'RED'
    BLUE  = 'BLUE'
    GREEN = 'GREEN'

for x in MyEnumType:
    print(x)

I get the following as expected:

MyEnumType.RED
MyEnumType.BLUE
MyEnumType.GREEN

Is it possible to create a class like this from a list or tuple that has been obtained from elsewhere?

Something vaguely similar to this perhaps:

myEnumStrings = ('RED', 'GREEN', 'BLUE')

class MyEnumType(str, Enum):
    def __init__(self):
        for x in myEnumStrings :
            self.setattr(self, x,x)

However, in the same way as in the original, I don't want to have to explicitly instantiate an object.

Will Da Silva · Accepted Answer · 2021-09-25 19:56:49Z

14

You can use the enum functional API for this:

from enum import Enum


myEnumStrings = ('RED', 'GREEN', 'BLUE')
MyEnumType = Enum('MyEnumType', myEnumStrings)

From the docs:

The first argument of the call to Enum is the name of the enumeration.

The second argument is the source of enumeration member names. It can be a whitespace-separated string of names, a sequence of names, a sequence of 2-tuples with key/value pairs, or a mapping (e.g. dictionary) of names to values.

answered Sep 25, 2021 at 19:56

Will Da Silva

7,1512 gold badges35 silver badges55 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

fundamental Over a year ago

nice - thank you. In addition, in order to get strings for the enum values as in the original, this does the trick: myEnumStrings = ( (x,x) for x in ('RED', 'GREEN', 'BLUE')).

thegreatcoder Over a year ago

How do I compare string values with the string enums with the above declaration? Example: 'RED'== MyEnumType.RED @fundamental @will-da-silva

thegreatcoder Over a year ago

Figured out. The way to do the comparison 'RED'== MyEnumType.RED: MyEnumType = Enum('MyEnumType', myEnumStrings, type=str)

Will Da Silva Over a year ago

@thegreatcoder You can also use enum.StrEnum without the type argument instead of enum.Enum to achieve this in Python 3.11+

Collectives™ on Stack Overflow

Create an enum class from a list of strings in Python

1 Answer 1

4 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

4 Comments

Your Answer

Sign up or log in

Post as a guest

Related