On Sun, 06 Mar 2011 12:59:55 -0800, Westley Martínez wrote: > I'm confused. Can someone tell me if we're talking about constant as in > 'fixed in memory' or as in 'you can't reassign' or both?
Python already has fixed in memory constants. They are immutable objects like strings, ints, floats, etc. Once you create a string "spam", you cannot modify it. This has been true about Python forever. What Python doesn't have is constant *names*. Once you bind an object to a name, like this: s = "spam" you can't modify the *object*, but you can rebind the name: s = "Nobody expects the Spanish Inquisition!" and now your code that expects s to be "spam" will fail. So the only new feature under discussion is a way to bind-once names, which many people call constants. Perhaps the name is not the best, since I'm sure some people will be surprised that you can do this: # hypothetical example const L = [1, 2, 3] L.append(4) # works del L[:] # works L = [] # fails but I call that a feature, not a bug. If you want an immutable constant, use a tuple, not a list. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
