cpython/Modules/_decimal
John Belmonte b0b836b20c
bpo-45995: add "z" format specifer to coerce negative 0 to zero (GH-30049)
Add "z" format specifier to coerce negative 0 to zero.

See https://github.com/python/cpython/issues/90153 (originally https://bugs.python.org/issue45995) for discussion.
This covers `str.format()` and f-strings.  Old-style string interpolation is not supported.

Co-authored-by: Mark Dickinson <dickinsm@gmail.com>
2022-04-11 15:34:18 +01:00
..
libmpdec bpo-41369: Finish updating the vendored libmpdec to version 2.5.1 (GH-24962) 2021-03-30 18:11:06 +02:00
tests bpo-45332: Fix broken Decimal test and benchmark (GH-28680) 2021-10-01 22:49:46 +09:00
_decimal.c bpo-45995: add "z" format specifer to coerce negative 0 to zero (GH-30049) 2022-04-11 15:34:18 +01:00
docstrings.h Revert "bpo-26680: Incorporate is_integer in all built-in and standard library numeric types (GH-6121)" (GH-22584) 2020-10-07 16:43:44 -07:00
README.txt Remove trailing whitespace. 2013-01-16 15:16:10 +01:00


About
=====

_decimal.c is a wrapper for the libmpdec library. libmpdec is a fast C
library for correctly-rounded arbitrary precision decimal floating point
arithmetic. It is a complete implementation of Mike Cowlishaw/IBM's
General Decimal Arithmetic Specification.


Build process for the module
============================

As usual, the build process for _decimal.so is driven by setup.py in the top
level directory. setup.py autodetects the following build configurations:

   1) x64         - 64-bit Python, x86_64 processor (AMD, Intel)

   2) uint128     - 64-bit Python, compiler provides __uint128_t (gcc)

   3) ansi64      - 64-bit Python, ANSI C

   4) ppro        - 32-bit Python, x86 CPU, PentiumPro or later

   5) ansi32      - 32-bit Python, ANSI C

   6) ansi-legacy - 32-bit Python, compiler without uint64_t

   7) universal   - Mac OS only (multi-arch)


It is possible to override autodetection by exporting:

   PYTHON_DECIMAL_WITH_MACHINE=value, where value is one of the above options.


NOTE
====

decimal.so is not built from a static libmpdec.a since doing so led to
failures on AIX (user report) and Windows (mixing static and dynamic CRTs
causes locale problems and more).