1268c1268,1270
<         self._negative_number_matcher = _re.compile(r'^-\d+$|^-\d*\.\d+$')
---
>         __negative_match_pattern  = r'^-\d+$|^-\d*\.\d+$|^-\d+\.\d*$|'
>         __negative_match_pattern += r'^-\d+[eE][+-]\d+$|^-\d*\.\d*[eE][+-]\d+$'
>         self._negative_number_matcher = _re.compile(__negative_match_pattern)