.. getthecode:: comparisons.py
    :language: python3
    :hidden:

=============
 Comparisons
=============

This page contains a memo on comparisons.


.. code-block:: py3

    from Tools import *
    
Let define some strings


.. code-block:: py3

    s0 = 'abc'
    s1 = 'def'
    
Let define a reference or alias to :code:`s0`


.. code-block:: py3

    s2 = s0
    
:code:`s0` and :code:`s2` have the same *id*, address of the object in memory.


.. code-block:: py3

    pretty_print([id(x) for x in (s0, s2, s1)])

.. code-block:: none

        [   139877472330784,
            139877472330784,
            139877471407664]
    

.. code-block:: py3

    print(id(s0) == id(s2))

.. code-block:: none

    True
    
Equality Test
-------------


.. code-block:: py3

    print(s0 != s1)

.. code-block:: none

    True
    

.. code-block:: py3

    print(s0 == s2)

.. code-block:: none

    True
    
Reference Test
--------------


.. code-block:: py3

    print(s0 is not s1)

.. code-block:: none

    True
    

.. code-block:: py3

    print(s0 is s2)

.. code-block:: none

    True
    
Comparison Tests
----------------


.. code-block:: py3

    x = 2
    print(0 <= x < 10)

.. code-block:: none

    True
    
shorter than


.. code-block:: py3

    0 <= x and x < 10