trictionary?

[Roy Smith]

Steven Bethard <steven.bethard at gmail.com> wrote:
> In Python, pairs are usually handled with tuples[2], but tuples would be 
> inconvenient in this case, since the first value must be modified.

Instead of modifying the tuple (which you can't do), you can create a new 
one:

a, b = myDict[key]
myDict[key] = (a+1, b)

It's a bit inefficient, but get it working first, with clear, easy to 
understand code, then worry about how efficient it is.  

> Declaring a class with two attributes as 
> you suggested is often a good substitute, but if the OP's code is really 
> what it looks like, I get another code smell because declaring a class 
> to be used by only 10 lines of code seems like overkill.

But, classes are so lightweight in Python.  You can get away with nothing 
more than:

class Data:
   pass

and then you can do things like:

myData = Data
myData.a = a
myData.b = b

More likely, I would want to write:

class Data:
   def __init__ (self, a, b):
      self.a = a
      self.b = b

but I've done the minimilist Data class more than once.  It doesn't cost 
much, and it's often more self-documenting than just a tuple.