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pythonsimplejson

Why does simplejson think this string is invalid json?


I'm trying to convert a simple JSON string {\n 100: {"a": "b"}\n} to a python object but its giving me this error: Expecting property name enclosed in double quotes

Why is it insisting that the name of the attribute be a string?

>>> import simplejson
>>> my_json = simplejson.loads('{\n    100: {"a": "b"}\n}')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/myuser/myenv/lib/python2.7/site-packages/simplejson/__init__.py", line 525, in loads
    return _default_decoder.decode(s)
  File "/Users/myuser/myenv/lib/python2.7/site-packages/simplejson/decoder.py", line 370, in decode
    obj, end = self.raw_decode(s)
  File "/Users/myuser/myenv/lib/python2.7/site-packages/simplejson/decoder.py", line 400, in raw_decode
    return self.scan_once(s, idx=_w(s, idx).end())
simplejson.errors.JSONDecodeError: Expecting property name enclosed in double quotes: line 2 column 5 (char 6)

Solution

  • This value is invalid {100: {"a": "b"}}, you need {"100": {"a": "b"}}.

    The property name there being 100 needs to be enclosed in double quotes so "100".

    Why is it insisting that the name of the attribute be a string?

    That's how JSON is.

    You may have been used to be able to write {100: {"a": "b"}} in Javascript or another language, (without double quoting the property name), but you'll still get a parsing error if you try to parse it as JSON in Javascript, e.g.:

    JSON.parse('{100: {"a": "b"}}')
    SyntaxError: JSON.parse: expected property name or '}'
    at line 1 column 2 of the JSON data