[Python-Dev] python optimization

[Greg Ewing]

Brett Cannon wrote:

>>I don't know to what extent these kind of optimizations are available to
>>cpython.  For example, are constant calculations removed from loops?
> 
> If you mean ``2+3``, then yes.

Actually, no. Constant folding *could* be done, but it currently isn't:

 >>> def f():
...   return 2+3
...
 >>> import dis
 >>> dis.dis(f)
   2           0 LOAD_CONST               1 (2)
               3 LOAD_CONST               2 (3)
               6 BINARY_ADD
               7 RETURN_VALUE
               8 LOAD_CONST               0 (None)
              11 RETURN_VALUE
 >>>

-- 
Greg Ewing, Computer Science Dept, +--------------------------------------+
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