diff options
Diffstat (limited to 'babel')
| -rw-r--r-- | babel/plural.py | 37 |
1 files changed, 30 insertions, 7 deletions
diff --git a/babel/plural.py b/babel/plural.py index 0b8e425..99e9a65 100644 --- a/babel/plural.py +++ b/babel/plural.py @@ -9,7 +9,6 @@ :license: BSD, see LICENSE for more details. """ import re -import sys from babel._compat import decimal @@ -19,10 +18,27 @@ _fallback_tag = 'other' def extract_operands(source): - """Extract operands from a decimal, a float or an int, according to - `CLDR rules`_. + """Extract operands from a decimal, a float or an int, according to `CLDR rules`_. + + The result is a 6-tuple (n, i, v, w, f, t), where those symbols are as follows: + + ====== =============================================================== + Symbol Value + ------ --------------------------------------------------------------- + n absolute value of the source number (integer and decimals). + i integer digits of n. + v number of visible fraction digits in n, with trailing zeros. + w number of visible fraction digits in n, without trailing zeros. + f visible fractional digits in n, with trailing zeros. + t visible fractional digits in n, without trailing zeros. + ====== =============================================================== .. _`CLDR rules`: http://www.unicode.org/reports/tr35/tr35-33/tr35-numbers.html#Operands + + :param source: A real number + :type source: int|float|decimal.Decimal + :return: A n-i-v-w-f-t tuple + :rtype: tuple[decimal.Decimal, int, int, int, int, int] """ n = abs(source) i = int(n) @@ -30,10 +46,17 @@ def extract_operands(source): if i == n: n = i else: - # 2.6's Decimal cannot convert from float directly - if sys.version_info < (2, 7): - n = str(n) - n = decimal.Decimal(n) + # Cast the `float` to a number via the string representation. + # This is required for Python 2.6 anyway (it will straight out fail to + # do the conversion otherwise), and it's highly unlikely that the user + # actually wants the lossless conversion behavior (quoting the Python + # documentation): + # > If value is a float, the binary floating point value is losslessly + # > converted to its exact decimal equivalent. + # > This conversion can often require 53 or more digits of precision. + # Should the user want that behavior, they can simply pass in a pre- + # converted `Decimal` instance of desired accuracy. + n = decimal.Decimal(str(n)) if isinstance(n, decimal.Decimal): dec_tuple = n.as_tuple() |