On 09/10/2012 16:30, Michele Lacchia wrote:

>
> A reason *not* to use '+' is that it would violate associativity
> in some cases, e.g.
>
> (path + "foo") + "bar"
>
> would not be the same as
>
> path + ("foo" + "bar")
>

I am missing something. Why not?

Because the result would be (respectively): path/foo/bar and path/foobar.

In the second example the two strings would be concatenated and only

then joined to the path.

This is a very good argument against the + operator!

But why not interpret a path as a tuple (not a list, it's immutable) of path segments and have:

path + ("foo", "bar")

and

path + ".tar.gz"

behave different (i.e. tuples add segments and strings add to the last segment)?

And of course path1 + path2 adds the segments together.

Joachim