"""JSON token scanner """ import re def _import_c_make_scanner(): try: raise ImportError # because assumes simplejson in path from simplejson._speedups import make_scanner return make_scanner except ImportError: return None c_make_scanner = _import_c_make_scanner() __all__ = ['make_scanner'] NUMBER_RE = re.compile( r'(-?(?:0|[1-9]\d*))(\.\d+)?([eE][-+]?\d+)?', (re.VERBOSE | re.MULTILINE | re.DOTALL)) def py_make_scanner(context): parse_object = context.parse_object parse_array = context.parse_array parse_string = context.parse_string match_number = NUMBER_RE.match encoding = context.encoding strict = context.strict parse_float = context.parse_float parse_int = context.parse_int parse_constant = context.parse_constant object_hook = context.object_hook object_pairs_hook = context.object_pairs_hook memo = context.memo def _scan_once(string, idx): try: nextchar = string[idx] except IndexError: raise StopIteration if nextchar == '"': return parse_string(string, idx + 1, encoding, strict) elif nextchar == '{': return parse_object((string, idx + 1), encoding, strict, _scan_once, object_hook, object_pairs_hook, memo) elif nextchar == '[': return parse_array((string, idx + 1), _scan_once) elif nextchar == 'n' and string[idx:idx + 4] == 'null': return None, idx + 4 elif nextchar == 't' and string[idx:idx + 4] == 'true': return True, idx + 4 elif nextchar == 'f' and string[idx:idx + 5] == 'false': return False, idx + 5 m = match_number(string, idx) if m is not None: integer, frac, exp = m.groups() if frac or exp: res = parse_float(integer + (frac or '') + (exp or '')) else: res = parse_int(integer) return res, m.end() elif nextchar == 'N' and string[idx:idx + 3] == 'NaN': return parse_constant('NaN'), idx + 3 elif nextchar == 'I' and string[idx:idx + 8] == 'Infinity': return parse_constant('Infinity'), idx + 8 elif nextchar == '-' and string[idx:idx + 9] == '-Infinity': return parse_constant('-Infinity'), idx + 9 else: raise StopIteration def scan_once(string, idx): try: return _scan_once(string, idx) finally: memo.clear() return scan_once make_scanner = c_make_scanner or py_make_scanner