=====
Usage
=====

To use Pyrofiler in a project::

    import pyrofiler

How pyrofiler works
-------------------

All pyrofiler's tools work in a same fashion: after calling the function (or code if it's a contextmanager) 
and measuring data, a `callback` object is called.

Here's the default callback that prints profiling results:

.. code-block:: python 

    def printer(result, description='Profile results'):
        print(description, ':', result)

Any arguments to a tool except the `callback` argument are passed
to the callback function.

Here's how the callback is called:

.. code-block:: python 

    callback(profiling_result, *args, **kwargs)

Where `args` and `kwargs` are arguments to the tool.

For example, this is the code for timing tool:


.. code-block:: python 

    def timing(*args, callback=printer, **kwargs) -> None:
        start = time()
        yield
        ellapsed_time = time() - start
        callback(ellapsed_time, *args, **kwargs)


Storing results in context
--------------------------

There is a special class `pyrofiler.Profiler` that uses 
special type of callbacks to aggregate data from all calls of tools.

.. code-block:: python 

    def cb(self, result, label, **kwargs):
        self.data[label] = result