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README.rst

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+==========
+positional
+==========
+
+|PyPi|
 
 |Build Status|
 
 |Documentation Status|
 
+Intro
+=====
+
+`positional` provides a decorator which enforces only some args may be passed
+positionally. The idea and some of the code was taken from the oauth2 client
+of the google-api client.
+
+The Basics
+==========
+
+The decorator makes it easy to support Python 3 style key-word only
+parameters. For example, in Python 3 it is possible to write:
+
+.. code:: python
+
+    >>> def fn(pos1, *, kwonly1 kwonly=None):
+    ...     ...
+
+All named parameters after `*` must be a keyword:
+
+.. code:: python
+
+    >>> fn(10, 'kw1', 'kw2')  # Raises exception.
+    >>> fn(10, kwonly1='kw1', kwonly2='kw2')  # Ok.
+
+To replicate this behaviour with the positional decorator you simply specify
+how many arguments may be passed positionally.
+
+Replicating the Example above:
+
+.. code:: python
+
+    >>> @positional(1)
+    ... fn(pos1, kwonly1=None, kwonly2=None):
+    ...     ...
+
+If no default value is provided to a keyword argument, it becomes a required
+keyword argument:
+
+.. code:: python
+
+    >>> @positional(0)
+    ... def fn(required_kw):
+    ...     ...
+
+This must be called with the keyword parameter:
+
+.. code:: python
+
+    >>> fn() # Raises exception
+    >>> fn(10) # Raises Exception
+    >>> fn(required_kw=10) # OK
+
+When defining instance or class methods always remember that in python the
+first positional argument passed is the instance; you will need to account for
+`self` and `cls`:
+
+.. code:: python
+
+    >>> class MyClass(object):
+    ...
+    ...     @positional(2)
+    ...     def my_method(self, pos1, kwonly1=None):
+    ...         ...
+    ...
+    ...     @classmethod
+    ...     @positional(2)
+    ...     def my_method(cls, pos1, kwonly1=None):
+    ...         ...
+
+
+
+If you would prefer not to account for `self` and `cls` you can use the
+`method` and `classmethod` helpers which do not consider the initial
+positional argument. So the following class is exactly the same as the one
+above:
+
+.. code:: python
+
+    >>> class MyClass(object):
+    ...
+    ...     @positional.method(1)
+    ...     def my_method(self, pos1, kwonly1=None):
+    ...         ...
+    ...
+    ...     @positional.classmethod(1)
+    ...     def my_method(cls, pos1, kwonly1=None):
+    ...         ...
+
+
+If a value isn't provided to the decorator then it will enforce that
+every variable without a default value will be required to be a kwarg:
+
+.. code:: python
+
+    >>> @positional()
+    ... def fn(pos1, kwonly1=None):
+    ...     ...
+    ...
+    >>> fn(10)  # Ok.
+    >>> fn(10, 20)  # Raises exception.
+    >>> fn(10, kwonly1=20)  # Ok.
+
+This behaviour will work with the `positional.method` and
+`positional.classmethod` helper functions as well:
+
+.. code:: python
+
+    >>> class MyClass(object):
+    ...
+    ...    @positional.classmethod()
+    ...    def my_method(cls, pos1, kwonly1=None):
+    ...        ...
+    ...
+    >>> MyClass.my_method(10)  # Ok.
+    >>> MyClass.my_method(10, 20)  # Raises exception.
+    >>> MyClass.my_method(10, kwonly1=20)  # Ok.
+
+For compatibility reasons you may wish to not always raise an exception so
+a WARN mode is available. Rather than raise an exception a warning message
+will be logged:
+
+.. code:: python
+
+    >>> @positional(1, enforcement=positional.WARN):
+    ... def fn(pos1, kwonly=1):
+    ...    ...
+
+
 .. |Build Status| image:: https://travis-ci.org/morganfainberg/positional.svg?branch=master
    :target: https://travis-ci.org/morganfainberg/positional
 .. |Documentation Status| image:: https://readthedocs.org/projects/positional/badge/?version=latest
    :target: http://positional.readthedocs.org/en/latest/?badge=latest
+.. |PyPi| image:: https://badge.fury.io/py/positional.png
+   :target: http://badge.fury.io/py/positional