[Python-Dev] [Python-checkins] cpython: Optimize string slicing to use the new API

["Martin v. Löwis"]

> +        result = PyUnicode_New(slicelength, PyUnicode_MAX_CHAR_VALUE(self));

This is incorrect: the maxchar of the slice might be smaller than the 
maxchar of the input string. So you'll need to iterate over the input 
string first, compute the maxchar, and then allocate the result string.

Or you allocate a temporary buffer of (1<<(kind-1)) * slicelength bytes,
copy the slice, allocate the target object with
PyUnicode_FromKindAndData, and release the temporary buffer.

Regards,
Martin