The Next Snake

With the latest major Python release, creator Guido van Rossum saw the opportunity to tidy up his famous scripting language. What is different about Python 3.0? In this article, I offer some highlights for Python programmers who are thinking about making the switch to 3.x.

The first important point is that version 3.0, which is also known as Python 3000 or Py3k, broke with an old tradition in that it is not downwardly compatible. According to von Rossum, "There is no requirement that Python 2.6 code will run unmodified on Python 3.0."

Python 2.6's main purpose is to take the pain out of switching versions. Many of Python 3.0's features were backported to Python 2.6. (A similar Python 2.7 version will accompany the recent Python 3.1 release.) In addition to these transitional 2.x versions, the 2to3 command-line tool supports programmers migrating code from Python 2.x to Python 3.x.

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