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Improves docs a bit #121

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merged 2 commits into from Jul 9, 2021
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Improves docs a bit #121

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65d473f
Improves docs a bit
sobolevn Jul 6, 2021
baa1b6f
Merge branch 'main' into patch-1
antonagestam Jul 9, 2021
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14 changes: 8 additions & 6 deletions docs/pages/getting-started.rst
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Expand Up @@ -4,7 +4,7 @@ Getting Started
Creating phantom types
----------------------

Phantom types are created by subclassing ``phantom.base.Phantom`` and providing a
Phantom types are created by subclassing :class:`phantom.base.Phantom` and providing a
predicate function.

.. code-block:: python
Expand Down Expand Up @@ -52,7 +52,9 @@ A motivating example
--------------------

Imagine that you're working on implementing a ``head()`` function that should return the
first item of any given iterable. You start out with a simple implementation::
first item of any given iterable. You start out with a simple implementation:

.. code-block:: python

def head(iterable: Iterable[T]) -> T:
return next(iter(iterable))
Expand All @@ -68,7 +70,7 @@ You need to deal with the problem at hand so you go ahead and adjust all the cal
of your function, and you now end up either asserting that the iterables are non-empty,
or catching the `StopIteration`.

::
.. code-block:: python

items = get_values()
if not len(items):
Expand All @@ -81,9 +83,9 @@ to check the length if the iterable for other purposes. Shotgun parsing is an
anti-pattern that results in a program state that is hard to predict and will very
likely lead to bugs down the line. So how should you deal with this?

Using phantom types you can use the builtin ``NonEmpty`` type.
Using phantom types you can use the builtin :class:`phantom.sized.NonEmpty` type.

::
.. code-block:: python

def head(iterable: NonEmpty[T]) -> T:
return next(iter(iterable))
Expand All @@ -96,7 +98,7 @@ By using the narrower type at the call sites, you avoid shotgun parsing, since t
logic further down in the processing chain can rely on the type as well, and you won't
need to check the length of the iterable again.

::
.. code-block:: python

items = get_values()
if not isinstance(items, NonEmpty):
Expand Down