Use Enum for constants

[0xjac]

Use Enum rather than variables or magic numbers for status and actions

I.e. go from this

if self.actions[0] == "y": # Payout next note ( NV11 only )

To something like:

Definition

class Status(Enum):
    OK = (1, "debug message ok")
    FAIL = (2, "debug message fail")
    # ...

    def __init__(self, value, debug_message):
        self.value = value
        self.debug_message = debug_message

    def __int__(self):
        return self.value

    def __eq__(self, other):
        return self.value == other

Usage

from sys import stderr

from constants import Status, Action


try:
    self.print_debug(Status(events.event).debug_message)
except ValueError:
    print('Unknown status: {}'.format(events.event), out=stderr)

if events.event == Status.SOME_STATUS:
    pass
    # do something custom
elif events.event == Status.SOME_OTHER_STATUS:
    pass
    # do something different
#...

This also gets rid of the from constants import * which is never a good idea

Credit to florv for the Enum class definition

[tshabs]

Just trying to maintain compatibility where convenient. For enum could use https://pypi.python.org/pypi/enum34/ for py2 (providing it doesn't cause problems)

[0xjac]

After some thinking I would advise to use the aenum package which is written by the same guy as the stdlib.enum and enum34 packages. It offers some advanced features and should solve all of the issues, including py2/py3 compatibility.

Here is a sample definition which suits your use case:

from aenum import IntEnum


class Status(IntEnum):
    _init_ = 'value', 'debug_message'
    
    OK = 1, "debug message ok"
    FAIL = 2, "debug message fail"

The _init_ takes a sequence of attributes to set on each Enum item. Then you just pass the actual values to each item.

Note that the first attribute passed to _init_ must be value.

I used IntEnum as the parent class in the example as this makes the enum a subclass of int as well but you can just use Enum if you prefer it.

In the end you should be able to use it like this with py2/py3:

assert Status.OK == Status(1)
assert Status.OK.name == 'OK'
assert Status.OK.value == 1
assert Status.OK.debug_message == "debug message ok"