The locale module opens access to the POSIX locale database
and functionality. The POSIX locale mechanism allows applications
to integrate certain cultural aspects into an applications, without
requiring the programmer to know all the specifics of each country
where the software is executed.
The locale module is implemented on top of the
_locale module, which in turn uses an
ANSI C locale implementation if available.
The locale module defines the following exception and
functions:
- setlocale (category[, value])
-
If value is specified, modifies the locale setting for the
category. The available categories are listed in the data
description below. The value is the name of a locale. An empty string
specifies the user's default settings. If the modification of the
locale fails, the exception Error is
raised. If successful, the new locale setting is returned.
If no value is specified, the current setting for the
category is returned.
setlocale() is not thread safe on most systems. Applications
typically start with a call of
import locale
locale.setlocale(locale.LC_ALL,"")
This sets the locale for all categories to the user's default setting
(typically specified in the LANG environment variable). If the
locale is not changed thereafter, using multithreading should not
cause problems.
- Error
-
Exception raised when setlocale() fails.
- localeconv ()
-
Returns the database of of the local conventions as a dictionary. This
dictionary has the following strings as keys:
- decimal_point specifies the decimal point used in
floating point number representations for the LC_NUMERIC
category.
- grouping is a sequence of numbers specifying at which
relative positions the thousands_sep is expected. If the
sequence is terminated with locale.CHAR_MAX, no further
grouping is performed. If the sequence terminates with a 0, the last
group size is repeatedly used.
- thousands_sep is the character used between groups.
- int_curr_symbol specifies the international currency
symbol from the LC_MONETARY category.
- currency_symbol is the local currency symbol.
- mon_decimal_point is the decimal point used in monetary
values.
- mon_thousands_sep is the separator for grouping of
monetary values.
- mon_grouping has the same format as the grouping
key; it is used for monetary values.
- positive_sign and negative_sign gives the sign
used for positive and negative monetary quantities.
- int_frac_digits and frac_digits specify the number
of fractional digits used in the international and local formatting
of monetary values.
- p_cs_precedes and n_cs_precedes specifies whether
the currency symbol precedes the value for positive or negative
values.
- p_sep_by_space and n_sep_by_space specifies
whether there is a space between the positive or negative value and
the currency symbol.
- p_sign_posn and n_sign_posn indicate how the
sign should be placed for positive and negative monetary values.
The possible values for p_sign_posn and n_sign_posn
are given below.
| Value |
Explanation |
|---|
0 |
Currency and value are surrounded by parentheses. |
1 |
The sign should precede the value and currency symbol. |
2 |
The sign should follow the value and currency symbol. |
3 |
The sign should immediately precede the value. |
4 |
The sign should immediately follow the value. |
LC_MAX |
Nothing is specified in this locale. |
- strcoll (string1,string2)
-
Compares two strings according to the current LC_COLLATE
setting. As any other compare function, returns a negative, or a
positive value, or 0, depending on whether string1
collates before or after string2 or is equal to it.
- strxfrm (string)
-
Transforms a string to one that can be used for the built-in function
cmp() , and still returns locale-aware
results. This function can be used when the same string is compared
repeatedly, e.g. when collating a sequence of strings.
- format (format, val, [grouping = 0])
-
Formats a number val according to the current
LC_NUMERIC setting. The format follows the conventions of
the % operator. For floating point values, the decimal point
is modified if appropriate. If grouping is true, also takes the
grouping into account.
- str (float)
-
Formats a floating point number using the same format as the built-in
function str(float), but takes the decimal point into
account.
- atof (string)
-
Converts a string to a floating point number, following the
LC_NUMERIC settings.
- atoi (string)
-
Converts a string to an integer, following the LC_NUMERIC
conventions.
- LC_CTYPE
-
Locale category for the character type functions. Depending on the
settings of this category, the functions of module string
dealing with case change their behaviour.
- LC_COLLATE
-
Locale category for sorting strings. The functions
strcoll() and strxfrm() of the locale
module are affected.
- LC_TIME
-
Locale category for the formatting of time. The function
time.strftime() follows these conventions.
- LC_MONETARY
-
Locale category for formatting of monetary values. The available
options are available from the localeconv() function.
- LC_MESSAGES
-
Locale category for message display. Python currently does not support
application specific locale-aware messages. Messages displayed by the
operating system, like those returned by os.strerror()
might be affected by this category.
- LC_NUMERIC
-
Locale category for formatting numbers. The functions
format(), atoi(), atof() and
str() of the locale module are affected by that
category. All other numeric formatting operations are not affected.
- LC_ALL
-
Combination of all locale settings. If this flag is used when the
locale is changed, setting the locale for all categories is
attempted. If that fails for any category, no category is changed at
all. When the locale is retrieved using this flag, a string indicating
the setting for all categories is returned. This string can be later
used to restore the settings.
- CHAR_MAX
-
This is a symbolic constant used for different values returned by
localeconv().
Example:
>>> import locale
>>> loc = locale.setlocale(locale.LC_ALL) # get current locale
>>> locale.setlocale(locale.LC_ALL, "de") # use German locale
>>> locale.strcoll("f\344n", "foo") # compare a string containing an umlaut
>>> locale.setlocale(locale.LC_ALL, "") # use user's preferred locale
>>> locale.setlocale(locale.LC_ALL, "C") # use default (C) locale
>>> locale.setlocale(locale.LC_ALL, loc) # restore saved locale
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