Robert Bradshaw wrote:
> There's a lot of work going on with loops right now, I've also  
> discovered http://trac.cython.org/cython_trac/ticket/243 . Another  
> problem is that we haven't nailed down exactly what the semantics for  
> the for...from loop should be. Should it be a C loop (where the  
> endpoint and step are re-evaluated every time, and changing the index  
> variable from the loop body modifies the loop behavior) or simply  
> alternative syntax for the for...in range() loop. I would say the  
> latter, (use a while loop if one wants the other behavior) but  
> certainly not some hybrid like we have now.

At least changing the value the iterator variable has after the loop 
"from C to Python semantics" (to use a phrase that's awfully familiar) 
would potentially break code. And then the semantics differ between the 
two anyway.

I think a case could be made that "for-from is the C for loop", and 
always reevaluate end/step.

However, myself I consider for-from present mostly for backwards 
compatability anyway, and so I don't really have an opinion about "the 
right" behaviour here.

-- 
Dag Sverre
_______________________________________________
Cython-dev mailing list
[email protected]
http://codespeak.net/mailman/listinfo/cython-dev

Reply via email to