Skip to content

gh-95994: Clarify escaped newlines. #96066

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
ezio-melotti merged 3 commits into from
Aug 26, 2022
Merged

gh-95994: Clarify escaped newlines. #96066

Changes from 1 commit
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
fd300cd
gh-95994: clarify escaped newlines.
ezio-melotti Aug 18, 2022
ec8b6ae
Rephrase ambiguous sentence.
ezio-melotti Aug 21, 2022
39fcfc1
Use `<newline>` in escape sequences table.
ezio-melotti Aug 26, 2022
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
Next Next commit
gh-95994: clarify escaped newlines.
  • Loading branch information
@ezio-melotti
ezio-melotti committed Aug 18, 2022
commit fd300cdd65f011ef7f1ec313eeb226bf2bb17624
34 changes: 23 additions & 11 deletions Doc/reference/lexical_analysis.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -552,7 +552,7 @@ Standard C. The recognized escape sequences are:
+-----------------+---------------------------------+-------+
| Escape Sequence | Meaning | Notes |
+=================+=================================+=======+
| ``\newline`` | Backslash and newline ignored | |
| ``\`` <LF> | Backslash and newline ignored | \(1) |
Comment thread
ezio-melotti marked this conversation as resolved.
Outdated
+-----------------+---------------------------------+-------+
| ``\\`` | Backslash (``\``) | |
+-----------------+---------------------------------+-------+
Expand All @@ -574,53 +574,65 @@ Standard C. The recognized escape sequences are:
+-----------------+---------------------------------+-------+
| ``\v`` | ASCII Vertical Tab (VT) | |
+-----------------+---------------------------------+-------+
| ``\ooo`` | Character with octal value | (1,3) |
| ``\ooo`` | Character with octal value | (2,4) |
| | *ooo* | |
+-----------------+---------------------------------+-------+
| ``\xhh`` | Character with hex value *hh* | (2,3) |
| ``\xhh`` | Character with hex value *hh* | (3,4) |
+-----------------+---------------------------------+-------+

Escape sequences only recognized in string literals are:

+-----------------+---------------------------------+-------+
| Escape Sequence | Meaning | Notes |
+=================+=================================+=======+
| ``\N{name}`` | Character named *name* in the | \(4) |
| ``\N{name}`` | Character named *name* in the | \(5) |
| | Unicode database | |
+-----------------+---------------------------------+-------+
| ``\uxxxx`` | Character with 16-bit hex value | \(5) |
| ``\uxxxx`` | Character with 16-bit hex value | \(6) |
| | *xxxx* | |
+-----------------+---------------------------------+-------+
| ``\Uxxxxxxxx`` | Character with 32-bit hex value | \(6) |
| ``\Uxxxxxxxx`` | Character with 32-bit hex value | \(7) |
| | *xxxxxxxx* | |
+-----------------+---------------------------------+-------+

Notes:

(1)
A backslash can be added at the end of a line to ignore the newline::

>>> 'This string will not include \
... backslashes or newline characters.'
'This string will not include backslashes or newline characters.'

The same result can be achieved by using parentheses and :ref:`string
literals concatenation <string-concatenation>` or :ref:`triple-quoted
strings <strings>`.
Comment thread
ezio-melotti marked this conversation as resolved.
Outdated


(2)
As in Standard C, up to three octal digits are accepted.

.. versionchanged:: 3.11
Octal escapes with value larger than ``0o377`` produce a :exc:`DeprecationWarning`.
In a future Python version they will be a :exc:`SyntaxWarning` and
eventually a :exc:`SyntaxError`.

(2)
(3)
Unlike in Standard C, exactly two hex digits are required.

(3)
(4)
In a bytes literal, hexadecimal and octal escapes denote the byte with the
given value. In a string literal, these escapes denote a Unicode character
with the given value.

(4)
(5)
.. versionchanged:: 3.3
Support for name aliases [#]_ has been added.

(5)
(6)
Exactly four hex digits are required.

(6)
(7)
Any Unicode character can be encoded this way. Exactly eight hex digits
are required.

Expand Down