This is, I guess, a few things the Python devs were just fed up with.
* "while 1" is now "while True"
* Types are compared with isinstance instead of ==
* Sort a list in one go with sorted()
My own twist is to also replace type('') with str, type(()) with tuple,
type([]) with list, type(1) with int, and type(5000.0) with float.
In py3k, imports are absolute unless using the "from . import" syntax.
This commit also solves a recursive import between Image, ImageColor, and
ImagePalette by delay-importing ImagePalette in Image.
I'm not too keen on this commit because the syntax is ugly. I might go back
and prefer the prettier "from PIL import".
What's really going on is that map() and filter() return iterators in py3k.
I've just gone ahead and turned them all into list comprehensions, because
I find them much easier to read.
y.has_key(x) is gone (use x in y), and keys(), values(), items(), and
range() all return views.
Some iterables needed to be packed into lists, either because the code
expected a list (such as "range(256) * 3") or because the original
collection was being modified (automatic global declarations).
The Tiff ImageFileDictionary is a special case and will be dealt with in
another commit.
Most of the differences are in tobytes/tostring naming and expected
behavior of the bytes() constructor. The latter was usually easy to fix
with the right bytes literal.
This is a good preview of what will have to happen in the Python 3 code.
This commit:
* Adds Python 3 module initialization functions. I split out the main init
of each module into a static setup_module function.
* Adds a py3.h which unifies int/long in Python 3 and unicode/bytes in
Python 2. _imagingft.c unfortunately looks a little kludgy after this
because it was already using PyUnicode functions, and I had to mix and
match there manually.
With this commit, the modules all build successfully under Python 3.
What this commit does NOT do is patch all of the uses of PyArg_ParseTuple
and Py_BuildValue, which all need to be checked for proper use of bytes
and unicode codes. It also does not let selftest.py run yet, because there
are probably hundreds of issues to fix in the Python code itself.