Probably this stems from the typical C-way of error-reporting out of a for-loop, which is to terminate earlier than the "regular loop condition", and hence a se

Probably this stems from the typical C-way of error-reporting out of a for-loop, which is to terminate earlier than the "regular loop condition", and hence a second test for the loop-condition can easily be used to check for abnormal termination... int i; for (i=0; i<length; i++) { if (is_broken(element[i])) break; process(element[i]); } /* if everything went fine, i == length, else we broke out early */ if (i < length) { fprintf(stderr,"Something was broken."); return -1; } Whereas the Python version obviously doesn't make sense in a pythonesque program iterating over sets of elements. for i in [1,2,3] : do_something(i) # ..now i is 3, not 4... obviously