# Tutorial

Please refer to RFC 6901 for the exact pointer syntax. `jsonpointer` has two interfaces. The `resolve_pointer` method is basically a deep `get`.

    >>> from jsonpointer import resolve_pointer
    >>> obj = {"foo": {"anArray": [ {"prop": 44}], "another prop": {"baz": "A string" }}}

    >>> resolve_pointer(obj, '') == obj
    True

    >>> resolve_pointer(obj, '/foo') == obj['foo']
    True

    >>> resolve_pointer(obj, '/foo/another prop') == obj['foo']['another prop']
    True

    >>> resolve_pointer(obj, '/foo/another prop/baz') == obj['foo']['another prop']['baz']
    True

    >>> resolve_pointer(obj, '/foo/anArray/0') == obj['foo']['anArray'][0]
    True

    >>> resolve_pointer(obj, '/some/path', None) == None
    True

The `set_pointer` method allows modifying a portion of an object using JSON pointer notation:

    >>> from jsonpointer import set_pointer
    >>> obj = {"foo": {"anArray": [ {"prop": 44}], "another prop": {"baz": "A string" }}}

    >>> set_pointer(obj, '/foo/anArray/0/prop', 55)
    {'foo': {'another prop': {'baz': 'A string'}, 'anArray': [{'prop': 55}]}}

    >>> obj
    {'foo': {'another prop': {'baz': 'A string'}, 'anArray': [{'prop': 55}]}}

By default `set_pointer` modifies the original object. Pass `inplace=False` to create a copy and modify the copy instead:

    >>> from jsonpointer import set_pointer
    >>> obj = {"foo": {"anArray": [ {"prop": 44}], "another prop": {"baz": "A string" }}}

    >>> set_pointer(obj, '/foo/anArray/0/prop', 55, inplace=False)
    {'foo': {'another prop': {'baz': 'A string'}, 'anArray': [{'prop': 55}]}}

    >>> obj
    {'foo': {'another prop': {'baz': 'A string'}, 'anArray': [{'prop': 44}]}}

The `JsonPointer` class wraps a (string) path and can be used to access the same path on several objects.

    >>> import jsonpointer

    >>> pointer = jsonpointer.JsonPointer('/foo/1')

    >>> obj1 = {'foo': ['a', 'b', 'c']}
    >>> pointer.resolve(obj1)
    'b'

    >>> obj2 = {'foo': {'0': 1, '1': 10, '2': 100}}
    >>> pointer.resolve(obj2)
    10