diff options
Diffstat (limited to 'Doc')
| -rw-r--r-- | Doc/library/decimal.rst | 10 | ||||
| -rw-r--r-- | Doc/library/functions.rst | 16 | ||||
| -rw-r--r-- | Doc/library/sys.rst | 12 | ||||
| -rw-r--r-- | Doc/reference/lexical_analysis.rst | 45 | ||||
| -rw-r--r-- | Doc/using/windows.rst | 21 | ||||
| -rw-r--r-- | Doc/whatsnew/3.6.rst | 28 |
6 files changed, 90 insertions, 42 deletions
diff --git a/Doc/library/decimal.rst b/Doc/library/decimal.rst index ee746e9..e984edc 100644 --- a/Doc/library/decimal.rst +++ b/Doc/library/decimal.rst @@ -345,7 +345,7 @@ Decimal objects *value* can be an integer, string, tuple, :class:`float`, or another :class:`Decimal` object. If no *value* is given, returns ``Decimal('0')``. If *value* is a string, it should conform to the decimal numeric string syntax after leading - and trailing whitespace characters are removed:: + and trailing whitespace characters, as well as underscores throughout, are removed:: sign ::= '+' | '-' digit ::= '0' | '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9' @@ -394,6 +394,10 @@ Decimal objects :class:`float` arguments raise an exception if the :exc:`FloatOperation` trap is set. By default the trap is off. + .. versionchanged:: 3.6 + Underscores are allowed for grouping, as with integral and floating-point + literals in code. + Decimal floating point objects share many properties with the other built-in numeric types such as :class:`float` and :class:`int`. All of the usual math operations and special methods apply. Likewise, decimal objects can be @@ -1075,8 +1079,8 @@ In addition to the three supplied contexts, new contexts can be created with the Decimal('4.44') This method implements the to-number operation of the IBM specification. - If the argument is a string, no leading or trailing whitespace is - permitted. + If the argument is a string, no leading or trailing whitespace or + underscores are permitted. .. method:: create_decimal_from_float(f) diff --git a/Doc/library/functions.rst b/Doc/library/functions.rst index db04b10..c4fcd98 100644 --- a/Doc/library/functions.rst +++ b/Doc/library/functions.rst @@ -271,6 +271,9 @@ are always available. They are listed here in alphabetical order. The complex type is described in :ref:`typesnumeric`. + .. versionchanged:: 3.6 + Grouping digits with underscores as in code literals is allowed. + .. function:: delattr(object, name) @@ -531,11 +534,14 @@ are always available. They are listed here in alphabetical order. The float type is described in :ref:`typesnumeric`. - .. index:: - single: __format__ - single: string; format() (built-in function) + .. versionchanged:: 3.6 + Grouping digits with underscores as in code literals is allowed. +.. index:: + single: __format__ + single: string; format() (built-in function) + .. function:: format(value[, format_spec]) Convert a *value* to a "formatted" representation, as controlled by @@ -702,6 +708,10 @@ are always available. They are listed here in alphabetical order. :meth:`base.__int__ <object.__int__>` instead of :meth:`base.__index__ <object.__index__>`. + .. versionchanged:: 3.6 + Grouping digits with underscores as in code literals is allowed. + + .. function:: isinstance(object, classinfo) Return true if the *object* argument is an instance of the *classinfo* diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst index 9460b84..6ee6c49 100644 --- a/Doc/library/sys.rst +++ b/Doc/library/sys.rst @@ -1104,18 +1104,6 @@ always available. thus may not be available in all Python implementations. -.. function:: settscdump(on_flag) - - Activate dumping of VM measurements using the Pentium timestamp counter, if - *on_flag* is true. Deactivate these dumps if *on_flag* is off. The function is - available only if Python was compiled with ``--with-tsc``. To understand - the output of this dump, read :file:`Python/ceval.c` in the Python sources. - - .. impl-detail:: - This function is intimately bound to CPython implementation details and - thus not likely to be implemented elsewhere. - - .. function:: set_coroutine_wrapper(wrapper) Allows intercepting creation of :term:`coroutine` objects (only ones that diff --git a/Doc/reference/lexical_analysis.rst b/Doc/reference/lexical_analysis.rst index 48f2043..a7c6a68 100644 --- a/Doc/reference/lexical_analysis.rst +++ b/Doc/reference/lexical_analysis.rst @@ -721,20 +721,24 @@ Integer literals Integer literals are described by the following lexical definitions: .. productionlist:: - integer: `decimalinteger` | `octinteger` | `hexinteger` | `bininteger` - decimalinteger: `nonzerodigit` `digit`* | "0"+ + integer: `decinteger` | `bininteger` | `octinteger` | `hexinteger` + decinteger: `nonzerodigit` (["_"] `digit`)* | "0"+ (["_"] "0")* + bininteger: "0" ("b" | "B") (["_"] `bindigit`)+ + octinteger: "0" ("o" | "O") (["_"] `octdigit`)+ + hexinteger: "0" ("x" | "X") (["_"] `hexdigit`)+ nonzerodigit: "1"..."9" digit: "0"..."9" - octinteger: "0" ("o" | "O") `octdigit`+ - hexinteger: "0" ("x" | "X") `hexdigit`+ - bininteger: "0" ("b" | "B") `bindigit`+ + bindigit: "0" | "1" octdigit: "0"..."7" hexdigit: `digit` | "a"..."f" | "A"..."F" - bindigit: "0" | "1" There is no limit for the length of integer literals apart from what can be stored in available memory. +Underscores are ignored for determining the numeric value of the literal. They +can be used to group digits for enhanced readability. One underscore can occur +between digits, and after base specifiers like ``0x``. + Note that leading zeros in a non-zero decimal number are not allowed. This is for disambiguation with C-style octal literals, which Python used before version 3.0. @@ -743,6 +747,10 @@ Some examples of integer literals:: 7 2147483647 0o177 0b100110111 3 79228162514264337593543950336 0o377 0xdeadbeef + 100_000_000_000 0b_1110_0101 + +.. versionchanged:: 3.6 + Underscores are now allowed for grouping purposes in literals. .. _floating: @@ -754,23 +762,28 @@ Floating point literals are described by the following lexical definitions: .. productionlist:: floatnumber: `pointfloat` | `exponentfloat` - pointfloat: [`intpart`] `fraction` | `intpart` "." - exponentfloat: (`intpart` | `pointfloat`) `exponent` - intpart: `digit`+ - fraction: "." `digit`+ - exponent: ("e" | "E") ["+" | "-"] `digit`+ + pointfloat: [`digitpart`] `fraction` | `digitpart` "." + exponentfloat: (`digitpart` | `pointfloat`) `exponent` + digitpart: `digit` (["_"] `digit`)* + fraction: "." `digitpart` + exponent: ("e" | "E") ["+" | "-"] `digitpart` Note that the integer and exponent parts are always interpreted using radix 10. For example, ``077e010`` is legal, and denotes the same number as ``77e10``. The -allowed range of floating point literals is implementation-dependent. Some -examples of floating point literals:: +allowed range of floating point literals is implementation-dependent. As in +integer literals, underscores are supported for digit grouping. + +Some examples of floating point literals:: - 3.14 10. .001 1e100 3.14e-10 0e0 + 3.14 10. .001 1e100 3.14e-10 0e0 3.14_15_93 Note that numeric literals do not include a sign; a phrase like ``-1`` is actually an expression composed of the unary operator ``-`` and the literal ``1``. +.. versionchanged:: 3.6 + Underscores are now allowed for grouping purposes in literals. + .. _imaginary: @@ -780,7 +793,7 @@ Imaginary literals Imaginary literals are described by the following lexical definitions: .. productionlist:: - imagnumber: (`floatnumber` | `intpart`) ("j" | "J") + imagnumber: (`floatnumber` | `digitpart`) ("j" | "J") An imaginary literal yields a complex number with a real part of 0.0. Complex numbers are represented as a pair of floating point numbers and have the same @@ -788,7 +801,7 @@ restrictions on their range. To create a complex number with a nonzero real part, add a floating point number to it, e.g., ``(3+4j)``. Some examples of imaginary literals:: - 3.14j 10.j 10j .001j 1e100j 3.14e-10j + 3.14j 10.j 10j .001j 1e100j 3.14e-10j 3.14_15_93j .. _operators: diff --git a/Doc/using/windows.rst b/Doc/using/windows.rst index 65c4b95..863d62d 100644 --- a/Doc/using/windows.rst +++ b/Doc/using/windows.rst @@ -747,10 +747,11 @@ populated on Windows: * If the environment variable :envvar:`PYTHONHOME` is set, it is assumed as "Python Home". Otherwise, the path of the main Python executable is used to - locate a "landmark file" (``Lib\os.py``) to deduce the "Python Home". If a - Python home is found, the relevant sub-directories added to :data:`sys.path` - (``Lib``, ``plat-win``, etc) are based on that folder. Otherwise, the core - Python path is constructed from the PythonPath stored in the registry. + locate a "landmark file" (either ``Lib\os.py`` or ``pythonXY.zip``) to deduce + the "Python Home". If a Python home is found, the relevant sub-directories + added to :data:`sys.path` (``Lib``, ``plat-win``, etc) are based on that + folder. Otherwise, the core Python path is constructed from the PythonPath + stored in the registry. * If the Python Home cannot be located, no :envvar:`PYTHONPATH` is specified in the environment, and no registry entries can be found, a default path with @@ -795,7 +796,8 @@ following advice will prevent conflicts with other installations: * If you cannot use the previous suggestions (for example, you are a distribution that allows people to run :file:`python.exe` directly), ensure that the landmark file (:file:`Lib\\os.py`) exists in your install directory. - (Note that it will not be detected inside a ZIP file.) + (Note that it will not be detected inside a ZIP file, but a correctly named + ZIP file will be detected instead.) These will ensure that the files in a system-wide installation will not take precedence over the copy of the standard library bundled with your application. @@ -803,10 +805,13 @@ Otherwise, your users may experience problems using your application. Note that the first suggestion is the best, as the other may still be susceptible to non-standard paths in the registry and user site-packages. -.. versionchanged:: 3.6 +.. versionchanged:: + 3.6 - Adds ``sys.path`` file support and removes ``applocal`` option from - ``pyvenv.cfg``. + * Adds ``sys.path`` file support and removes ``applocal`` option from + ``pyvenv.cfg``. + * Adds ``pythonXX.zip`` as a potential landmark when directly adjacent + to the executable. Additional modules ================== diff --git a/Doc/whatsnew/3.6.rst b/Doc/whatsnew/3.6.rst index 8a57110..ac50137 100644 --- a/Doc/whatsnew/3.6.rst +++ b/Doc/whatsnew/3.6.rst @@ -101,6 +101,11 @@ Windows improvements: which means that when the 260 character path limit may no longer apply. See :ref:`removing the MAX_PATH limitation <max-path>` for details. +* A ``sys.path`` file can be added to force isolated mode and fully specify + all search paths to avoid registry and environment lookup. + +* A ``python36.zip`` file now works as a landmark to infer :envvar:`PYTHONHOME` + .. PEP-sized items next. .. _pep-4XX: @@ -124,6 +129,29 @@ Windows improvements: New Features ============ +.. _pep-515: + +PEP 515: Underscores in Numeric Literals +======================================== + +Prior to PEP 515, there was no support for writing long numeric +literals with some form of separator to improve readability. For +instance, how big is ``1000000000000000```? With :pep:`515`, though, +you can use underscores to separate digits as desired to make numeric +literals easier to read: ``1_000_000_000_000_000``. Underscores can be +used with other numeric literals beyond integers, e.g. +``0x_FF_FF_FF_FF``. + +Single underscores are allowed between digits and after any base +specifier. More than a single underscore in a row, leading, or +trailing underscores are not allowed. + +.. seealso:: + + :pep:`523` - Underscores in Numeric Literals + PEP written by Georg Brandl & Serhiy Storchaka. + + .. _pep-523: PEP 523: Adding a frame evaluation API to CPython |