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Sat Apr 27 04:59:23 CEST 2013 · https://mail.python.org/pipermail/python-dev/2013-April/125624.html

On 04/26/2013 11:17 AM, Eli Bendersky wrote:

> I feel that this thread has lost track of it long ago. Some time back in the Enum discussions (some 350 messages ago or
> so), there was a proposal to have this:
>
> class Color(Enum):
>    RED, BLUE, GREEN
>
> By doing some crazy-cool shenanigans. Although the syntax is great, it was rejected on the basis of being too magic.

Although explicit reasons were not mentioned (and perhaps not even consciously recognized -- *sigh* someday I hope to be 
that good),
there are very good ones beyond "being too magic" -- way too easy to introduce bugs:  name lookup success looks exactly 
like name lookup failure, but the consequences were drastically different:

class Color(Enum):
     BLACK
     RED
     GREEN
     BLUE

class MoreColor(Enum):
     BLACK
     CYAN
     MAGENTA
     YELLOW

BLACK in MoreColor is a bug that cannot easily be detected as it is a successful name lookup; the consequence is that 
CYAN, MAGENTA, and YELLOW are now off by one.

Not being Dutch, I had to smack into that one before I gave up on the idea.

--
~Ethan~

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Showing content from https://mail.python.org/pipermail/python-dev/2013-April/125624.html below:

[Python-Dev] PEP 435 -- Adding an Enum type to the Python standard library