versions if they're not defined.

Added a new macro, Py_IS_FINITE(X).  On windows there is an intrinsic for this and it is more efficient than to use !Py_IS_INFINITE(X) && !Py_IS_NAN(X).  No change on other platforms

strings too... (thanks to georg brandl for spotting the exact problem
faster than anyone else)

(the unicode versions of these are still 2x faster on windows,
though...)

based on work by Andrew Dalke, with tweaks by yours truly.

statement raise SyntaxError, and add testcase.

(SF patch #1281291, contributed by Rory Yorke)

``long(str, base)`` is now up to 6x faster for non-power-of-2 bases.  The
largest speedup is for inputs with about 1000 decimal digits.  Conversion
from non-power-of-2 bases remains quadratic-time in the number of input
digits (it was and remains linear-time for bases 2, 4, 8, 16 and 32).

Speedups at various lengths for decimal inputs, comparing 2.4.3 with
current trunk.  Note that it's actually a bit slower for 1-digit strings:

  len  speedup
 ----  -------
   1     -4.5%
   2      4.6%
   3      8.3%
   4     12.7%
   5     16.9%
   6     28.6%
   7     35.5%
   8     44.3%
   9     46.6%
  10     55.3%
  11     65.7%
  12     77.7%
  13     73.4%
  14     75.3%
  15     85.2%
  16    103.0%
  17     95.1%
  18    112.8%
  19    117.9%
  20    128.3%
  30    174.5%
  40    209.3%
  50    236.3%
  60    254.3%
  70    262.9%
  80    295.8%
  90    297.3%
 100    324.5%
 200    374.6%
 300    403.1%
 400    391.1%
 500    388.7%
 600    440.6%
 700    468.7%
 800    498.0%
 900    507.2%
1000    501.2%
2000    450.2%
3000    463.2%
4000    452.5%
5000    440.6%
6000    439.6%
7000    424.8%
8000    418.1%
9000    417.7%

be make to pass now for unicode if it passes for str, or
vice versa.

the Need For Speed sprint coding.  Includes commented out overflow tests
which will be uncommented once the code is fixed.

This test will break the 8-bit string tests because
    "".replace("", "A") == "" when it should == "A"

We have a fix for it, which should be added tomorrow.

constant-length changes; use fastsearch to locate the first match.

results in a 2.5x speedup on the stringbench count tests, and a 20x (!)
speedup on the stringbench search/find/contains test, compared to 2.5a2.

for more on the algorithm, see:

    http://effbot.org/zone/stringlib.htm

if you get weird results, you can disable the new algoritm by undefining
USE_FAST in Objects/unicodeobject.c.

enjoy /F

due to a module-level cache.  Clearing the cache should
make it stop showing up in refleak reports.

`struct` module changes).