Adding @inject decorator docs

docs/advanced_usage/index.rst

@@ -0,0 +1,28 @@
+
+Advanced usage
+==============
+
+Current section of documentation describes advanced usage of *Objects*.
+
+@inject decorator
+-----------------
+
+``@inject`` decorator can be used for making *inline* dependency injections.
+It *patches* decorated callable in such way that dependency injection will be
+done during every call of decorated callable.
+
+``@inject`` decorator takes only argument that is supposed to be an
+``objects.injections.KwArg`` injection.
+
+Any Python object will be injected *as is*, except *Objects* providers,
+that will be called to provide injectable value.
+
+Example:
+
+.. literalinclude:: ../../examples/advanced_usage/inject_decorator_simple.py
+   :language: python
+
+Example of dependecy injection in Flask view:
+
+.. literalinclude:: ../../examples/advanced_usage/inject_decorator_flask.py
+   :language: python

examples/advanced_usage/inject_decorator_simple.py

@@ -1,4 +1,4 @@
-"""`@inject()` decorator simple example."""
+"""`@inject` decorator simple example."""
 
 from objects.providers import Factory
 from objects.injections import KwArg