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bpo-30052: Link bytes & bytearray to stdtypes not functions (GH-1271
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Builtin container types have two potential link targets in the docs:

- their entry in the list of builtin callables
- their type documentation

This change brings `bytes` and `bytearray` into line with other
container types by having cross-references default to linking to
their type documentation, rather than their builtin callable entry.
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csabella authored and ncoghlan committed Apr 26, 2017
1 parent d819ad9 commit c6db481
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Showing 3 changed files with 98 additions and 89 deletions.
9 changes: 6 additions & 3 deletions Doc/library/functions.rst
Expand Up @@ -16,8 +16,8 @@ are always available. They are listed here in alphabetical order.
:func:`ascii` :func:`enumerate` :func:`input` :func:`oct` :func:`staticmethod`
:func:`bin` :func:`eval` :func:`int` :func:`open` |func-str|_
:func:`bool` :func:`exec` :func:`isinstance` :func:`ord` :func:`sum`
:func:`bytearray` :func:`filter` :func:`issubclass` :func:`pow` :func:`super`
:func:`bytes` :func:`float` :func:`iter` :func:`print` |func-tuple|_
|func-bytearray|_ :func:`filter` :func:`issubclass` :func:`pow` :func:`super`
|func-bytes|_ :func:`float` :func:`iter` :func:`print` |func-tuple|_
:func:`callable` :func:`format` :func:`len` :func:`property` :func:`type`
:func:`chr` |func-frozenset|_ |func-list|_ |func-range|_ :func:`vars`
:func:`classmethod` :func:`getattr` :func:`locals` :func:`repr` :func:`zip`
Expand All @@ -37,7 +37,8 @@ are always available. They are listed here in alphabetical order.
.. |func-str| replace:: ``str()``
.. |func-tuple| replace:: ``tuple()``
.. |func-range| replace:: ``range()``

.. |func-bytearray| replace:: ``bytearray()``
.. |func-bytes| replace:: ``bytes()``

.. function:: abs(x)

Expand Down Expand Up @@ -99,6 +100,7 @@ are always available. They are listed here in alphabetical order.

.. _func-bytearray:
.. class:: bytearray([source[, encoding[, errors]]])
:noindex:

Return a new array of bytes. The :class:`bytearray` class is a mutable
sequence of integers in the range 0 <= x < 256. It has most of the usual
Expand Down Expand Up @@ -128,6 +130,7 @@ are always available. They are listed here in alphabetical order.

.. _func-bytes:
.. class:: bytes([source[, encoding[, errors]]])
:noindex:

Return a new "bytes" object, which is an immutable sequence of integers in
the range ``0 <= x < 256``. :class:`bytes` is an immutable version of
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162 changes: 84 additions & 78 deletions Doc/library/stdtypes.rst
Expand Up @@ -2265,8 +2265,8 @@ The :mod:`array` module supports efficient storage of basic data types like

.. _typebytes:

Bytes
-----
Bytes Objects
-------------

.. index:: object: bytes

Expand All @@ -2275,69 +2275,71 @@ binary protocols are based on the ASCII text encoding, bytes objects offer
several methods that are only valid when working with ASCII compatible
data and are closely related to string objects in a variety of other ways.

Firstly, the syntax for bytes literals is largely the same as that for string
literals, except that a ``b`` prefix is added:
.. class:: bytes([source[, encoding[, errors]]])

* Single quotes: ``b'still allows embedded "double" quotes'``
* Double quotes: ``b"still allows embedded 'single' quotes"``.
* Triple quoted: ``b'''3 single quotes'''``, ``b"""3 double quotes"""``
Firstly, the syntax for bytes literals is largely the same as that for string
literals, except that a ``b`` prefix is added:

Only ASCII characters are permitted in bytes literals (regardless of the
declared source code encoding). Any binary values over 127 must be entered
into bytes literals using the appropriate escape sequence.
* Single quotes: ``b'still allows embedded "double" quotes'``
* Double quotes: ``b"still allows embedded 'single' quotes"``.
* Triple quoted: ``b'''3 single quotes'''``, ``b"""3 double quotes"""``

As with string literals, bytes literals may also use a ``r`` prefix to disable
processing of escape sequences. See :ref:`strings` for more about the various
forms of bytes literal, including supported escape sequences.
Only ASCII characters are permitted in bytes literals (regardless of the
declared source code encoding). Any binary values over 127 must be entered
into bytes literals using the appropriate escape sequence.

While bytes literals and representations are based on ASCII text, bytes
objects actually behave like immutable sequences of integers, with each
value in the sequence restricted such that ``0 <= x < 256`` (attempts to
violate this restriction will trigger :exc:`ValueError`. This is done
deliberately to emphasise that while many binary formats include ASCII based
elements and can be usefully manipulated with some text-oriented algorithms,
this is not generally the case for arbitrary binary data (blindly applying
text processing algorithms to binary data formats that are not ASCII
compatible will usually lead to data corruption).
As with string literals, bytes literals may also use a ``r`` prefix to disable
processing of escape sequences. See :ref:`strings` for more about the various
forms of bytes literal, including supported escape sequences.

In addition to the literal forms, bytes objects can be created in a number of
other ways:
While bytes literals and representations are based on ASCII text, bytes
objects actually behave like immutable sequences of integers, with each
value in the sequence restricted such that ``0 <= x < 256`` (attempts to
violate this restriction will trigger :exc:`ValueError`. This is done
deliberately to emphasise that while many binary formats include ASCII based
elements and can be usefully manipulated with some text-oriented algorithms,
this is not generally the case for arbitrary binary data (blindly applying
text processing algorithms to binary data formats that are not ASCII
compatible will usually lead to data corruption).

* A zero-filled bytes object of a specified length: ``bytes(10)``
* From an iterable of integers: ``bytes(range(20))``
* Copying existing binary data via the buffer protocol: ``bytes(obj)``
In addition to the literal forms, bytes objects can be created in a number of
other ways:

Also see the :ref:`bytes <func-bytes>` built-in.
* A zero-filled bytes object of a specified length: ``bytes(10)``
* From an iterable of integers: ``bytes(range(20))``
* Copying existing binary data via the buffer protocol: ``bytes(obj)``

Since 2 hexadecimal digits correspond precisely to a single byte, hexadecimal
numbers are a commonly used format for describing binary data. Accordingly,
the bytes type has an additional class method to read data in that format:
Also see the :ref:`bytes <func-bytes>` built-in.

.. classmethod:: bytes.fromhex(string)
Since 2 hexadecimal digits correspond precisely to a single byte, hexadecimal
numbers are a commonly used format for describing binary data. Accordingly,
the bytes type has an additional class method to read data in that format:

This :class:`bytes` class method returns a bytes object, decoding the
given string object. The string must contain two hexadecimal digits per
byte, with ASCII whitespace being ignored.
.. classmethod:: fromhex(string)

>>> bytes.fromhex('2Ef0 F1f2 ')
b'.\xf0\xf1\xf2'
This :class:`bytes` class method returns a bytes object, decoding the
given string object. The string must contain two hexadecimal digits per
byte, with ASCII whitespace being ignored.

.. versionchanged:: 3.7
:meth:`bytes.fromhex` now skips all ASCII whitespace in the string,
not just spaces.
>>> bytes.fromhex('2Ef0 F1f2 ')
b'.\xf0\xf1\xf2'

A reverse conversion function exists to transform a bytes object into its
hexadecimal representation.
.. versionchanged:: 3.7
:meth:`bytes.fromhex` now skips all ASCII whitespace in the string,
not just spaces.

.. method:: bytes.hex()
A reverse conversion function exists to transform a bytes object into its
hexadecimal representation.

Return a string object containing two hexadecimal digits for each
byte in the instance.
.. method:: hex()

>>> b'\xf0\xf1\xf2'.hex()
'f0f1f2'
Return a string object containing two hexadecimal digits for each
byte in the instance.

.. versionadded:: 3.5
>>> b'\xf0\xf1\xf2'.hex()
'f0f1f2'

.. versionadded:: 3.5

Since bytes objects are sequences of integers (akin to a tuple), for a bytes
object *b*, ``b[0]`` will be an integer, while ``b[0:1]`` will be a bytes
Expand Down Expand Up @@ -2367,49 +2369,53 @@ Bytearray Objects
.. index:: object: bytearray

:class:`bytearray` objects are a mutable counterpart to :class:`bytes`
objects. There is no dedicated literal syntax for bytearray objects, instead
they are always created by calling the constructor:
objects.

* Creating an empty instance: ``bytearray()``
* Creating a zero-filled instance with a given length: ``bytearray(10)``
* From an iterable of integers: ``bytearray(range(20))``
* Copying existing binary data via the buffer protocol: ``bytearray(b'Hi!')``
.. class:: bytearray([source[, encoding[, errors]]])

As bytearray objects are mutable, they support the
:ref:`mutable <typesseq-mutable>` sequence operations in addition to the
common bytes and bytearray operations described in :ref:`bytes-methods`.
There is no dedicated literal syntax for bytearray objects, instead
they are always created by calling the constructor:

Also see the :ref:`bytearray <func-bytearray>` built-in.
* Creating an empty instance: ``bytearray()``
* Creating a zero-filled instance with a given length: ``bytearray(10)``
* From an iterable of integers: ``bytearray(range(20))``
* Copying existing binary data via the buffer protocol: ``bytearray(b'Hi!')``

Since 2 hexadecimal digits correspond precisely to a single byte, hexadecimal
numbers are a commonly used format for describing binary data. Accordingly,
the bytearray type has an additional class method to read data in that format:
As bytearray objects are mutable, they support the
:ref:`mutable <typesseq-mutable>` sequence operations in addition to the
common bytes and bytearray operations described in :ref:`bytes-methods`.

.. classmethod:: bytearray.fromhex(string)
Also see the :ref:`bytearray <func-bytearray>` built-in.

This :class:`bytearray` class method returns bytearray object, decoding
the given string object. The string must contain two hexadecimal digits
per byte, with ASCII whitespace being ignored.
Since 2 hexadecimal digits correspond precisely to a single byte, hexadecimal
numbers are a commonly used format for describing binary data. Accordingly,
the bytearray type has an additional class method to read data in that format:

>>> bytearray.fromhex('2Ef0 F1f2 ')
bytearray(b'.\xf0\xf1\xf2')
.. classmethod:: fromhex(string)

.. versionchanged:: 3.7
:meth:`bytearray.fromhex` now skips all ASCII whitespace in the string,
not just spaces.
This :class:`bytearray` class method returns bytearray object, decoding
the given string object. The string must contain two hexadecimal digits
per byte, with ASCII whitespace being ignored.

A reverse conversion function exists to transform a bytearray object into its
hexadecimal representation.
>>> bytearray.fromhex('2Ef0 F1f2 ')
bytearray(b'.\xf0\xf1\xf2')

.. method:: bytearray.hex()
.. versionchanged:: 3.7
:meth:`bytearray.fromhex` now skips all ASCII whitespace in the string,
not just spaces.

Return a string object containing two hexadecimal digits for each
byte in the instance.
A reverse conversion function exists to transform a bytearray object into its
hexadecimal representation.

>>> bytearray(b'\xf0\xf1\xf2').hex()
'f0f1f2'
.. method:: hex()

Return a string object containing two hexadecimal digits for each
byte in the instance.

.. versionadded:: 3.5
>>> bytearray(b'\xf0\xf1\xf2').hex()
'f0f1f2'

.. versionadded:: 3.5

Since bytearray objects are sequences of integers (akin to a list), for a
bytearray object *b*, ``b[0]`` will be an integer, while ``b[0:1]`` will be
Expand Down
16 changes: 8 additions & 8 deletions Doc/reference/datamodel.rst
Expand Up @@ -320,9 +320,9 @@ Sequences

A bytes object is an immutable array. The items are 8-bit bytes,
represented by integers in the range 0 <= x < 256. Bytes literals
(like ``b'abc'``) and the built-in function :func:`bytes` can be used to
construct bytes objects. Also, bytes objects can be decoded to strings
via the :meth:`~bytes.decode` method.
(like ``b'abc'``) and the built-in :func:`bytes()` constructor
can be used to create bytes objects. Also, bytes objects can be
decoded to strings via the :meth:`~bytes.decode` method.

Mutable sequences
.. index::
Expand All @@ -349,9 +349,9 @@ Sequences
.. index:: bytearray

A bytearray object is a mutable array. They are created by the built-in
:func:`bytearray` constructor. Aside from being mutable (and hence
unhashable), byte arrays otherwise provide the same interface and
functionality as immutable bytes objects.
:func:`bytearray` constructor. Aside from being mutable
(and hence unhashable), byte arrays otherwise provide the same interface
and functionality as immutable :class:`bytes` objects.

.. index:: module: array

Expand Down Expand Up @@ -1253,8 +1253,8 @@ Basic customization

.. index:: builtin: bytes

Called by :func:`bytes` to compute a byte-string representation of an
object. This should return a ``bytes`` object.
Called by :ref:`bytes <func-bytes>` to compute a byte-string representation
of an object. This should return a :class:`bytes` object.

.. index::
single: string; __format__() (object method)
Expand Down

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