[Python-Dev] Switch statement

Fredrik Lundh fredrik at pythonware.com
Wed Jun 21 20:59:03 CEST 2006

Fredrik Lundh wrote:

>> But in most cases the 'constant' is actually an expression involving a
>> global, often even a global in another module. (E.g. sre_compile.py)
>> The compiler will have a hard time proving that this is really a
>> constant, so it won't optimize the code.
> unless we come up with a way to make it possible to mark an variable as 
> a constant.

such as the primary

     'constant' expr

which simply means that expr will be evaluated at function definition 
time, rather than at runtime.  example usage:

     var = expression
     if var == constant sre.FOO:
     elif var == constant sre.BAR:
     elif var in constant (sre.FIE, sre.FUM):


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