Programmatically creating variables in Python [duplicate]

Answer 1

Don't try to stick this into a global variable. It's horrid. Do this instead.

import string

variables = {}
for x in string.ascii_uppercase:
    variables[x] = Variable(x)

The you access it from variables['Q'], for example.

If you want attribute access you can do:

class Variables(object): pass

and

variables = Variables()
for x in string.ascii_uppercase:
    setattr(variables, x) = Variable(x)

But in that case I'd rather create them dynamically in a Variables container class.

import string

class Variable(object):
    def __init__(self, value):
        self.value = value
    def __repr__(self):
        return "" % self.value

class Variables(object):
    def __getattr__(self, n):
        if n in string.ascii_uppercase:
            v = Variable(n)
            setattr(self, n, v)
            return v
        raise AttributeError("Variables instance has no attribute %s" % n)

Usage:

>>> v = Variables()
>>> v.G

>>> v.Y

>>> v.G is v.G
True

Simple and clean, no ugly hacks (well, except a getattr, and it's not that ugly), and you don't even have to make the Variables you don't need.