Sharing code between different projects?

[andrea crotti]

I am in the situation where I am working on different projects that
might potentially share a lot of code.

I started to work on project A, then switched completely to project B
and in the transiction I copied over a lot of code with the
corresponding tests, and I started to modify it.

Now it's time to work again on project A, but I don't want to copy
things over again.

I would like to design a simple and nice way to share between projects,
where the things I want to share are simple but useful things as for
example:

class TempDirectory:
    """Create a temporary directory and cd to it on enter, cd back to
    the original position and remove it on exit
    """
    def __init__(self):
        self.oldcwd = getcwd()
        self.temp_dir = mkdtemp()

    def __enter__(self):
        logger.debug("create and move to temp directory %s" % self.temp_dir)
        return self.temp_dir

    def __exit__(self, type, value, traceback):
        # I first have to move out
        chdir(self.oldcwd)
        logger.debug("removing the temporary directory and go back to
the original position %s" % self.temp_dir)
        rmtree(self.temp_dir)


The problem is that there are functions/classes from many domains, so it
would not make much sense to create a real project, and the only name I
could give might be "utils or utilities"..

In plus the moment the code is shared I must take care of versioning and
how to link different pieces together (we use perforce by the way).

If then someone else except me will want to use these functions then of
course I'll have to be extra careful, designing really good API's and so
on, so I'm wondering where I should set the trade-off between ability to
share and burden to maintain..

Anyone has suggestions/real world experiences about this?