diff options
Diffstat (limited to 'lib/simplejson/scanner.py')
| -rw-r--r-- | lib/simplejson/scanner.py | 77 | 
1 files changed, 77 insertions, 0 deletions
| diff --git a/lib/simplejson/scanner.py b/lib/simplejson/scanner.py new file mode 100644 index 000000000..54593a371 --- /dev/null +++ b/lib/simplejson/scanner.py @@ -0,0 +1,77 @@ +"""JSON token scanner +""" +import re +def _import_c_make_scanner(): +    try: +        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 | 
