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-rw-r--r--modules/language/python/module/json/scanner.py72
1 files changed, 72 insertions, 0 deletions
diff --git a/modules/language/python/module/json/scanner.py b/modules/language/python/module/json/scanner.py
new file mode 100644
index 0000000..bd6a91a
--- /dev/null
+++ b/modules/language/python/module/json/scanner.py
@@ -0,0 +1,72 @@
+module(json, scanner)
+
+"""JSON token scanner
+"""
+import re
+c_make_scanner = None
+
+__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
+ 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, strict)
+ elif nextchar == '{':
+ return parse_object((string, idx + 1), 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