.. role:: py(code) :language: python

Listish

.. image:: https://circleci.com/gh/funkyHat/listish.svg?style=svg :target: https://circleci.com/gh/funkyHat/listish

:py:listish.Listish is a list-behaviour wrapper for arbitrary sequences and iterables (including iterators).

It acts as a mutable data wrapper for arbitrary inputs. On top of non-indexable input it also adds indexability.

Any iterable (including iterators) is supported:

.. code-block:: python

>>> g = (x*7-1 for x in [6,2,1,7,9,33])
>>> l = Listish(g)
>>> l[3]
48

Complex slicing is supported:

.. code-block:: python

>>> l = Listish(x for x in range(100) if x % 3)
>>> l[0:20:2]
[1, 4, 7, 10, 13, 16, 19, 22, 25, 28]

The input is used somewhat efficiently, only scanning far enough to retrieve the requested index:

.. code-block:: python

>>> r = (x for x in range(10))
>>> l = Listish(r)
>>> l[4]
4
>>> next(r)
5
>>> print(warning)
In practise interfering with an iterable after passing it to this library is a bad idea, as we can see
>>> l[5]
6

Tupleish

:py:listish.Tupleish provides indexing & persistence while presenting an immutable interface. :py:listish.Listish inherits most of its functionality from :py:listish.Tupleish, which is provided as a separate class for some kind of completeness.

See Also

:py:itertools.tee, in the standard library, provides n iterables which proxy the same input iterable, while using the minimum required memory, which may be more suitable for some use cases than :py:Listish or :py:Tupleish, though it does not attempt to add enumerability or mutability.