xref: /openbsd/gnu/usr.bin/perl/lib/locale.pm (revision 264ca280)
1package locale;
2
3our $VERSION = '1.03';
4use Config;
5
6$Carp::Internal{ (__PACKAGE__) } = 1;
7
8=head1 NAME
9
10locale - Perl pragma to use or avoid POSIX locales for built-in operations
11
12=head1 SYNOPSIS
13
14    @x = sort @y;      # Native-platform/Unicode code point sort order
15    {
16        use locale;
17        @x = sort @y;  # Locale-defined sort order
18    }
19    @x = sort @y;      # Native-platform/Unicode code point sort order
20                       # again
21
22=head1 DESCRIPTION
23
24This pragma tells the compiler to enable (or disable) the use of POSIX
25locales for built-in operations (for example, LC_CTYPE for regular
26expressions, LC_COLLATE for string comparison, and LC_NUMERIC for number
27formatting).  Each "use locale" or "no locale"
28affects statements to the end of the enclosing BLOCK.
29
30See L<perllocale> for more detailed information on how Perl supports
31locales.
32
33On systems that don't have locales, this pragma will cause your operations
34to behave as if in the "C" locale; attempts to change the locale will fail.
35
36=cut
37
38# A separate bit is used for each of the two forms of the pragma, as they are
39# mostly independent, and interact with each other and the unicode_strings
40# feature.  This allows for fast determination of which one(s) of the three
41# are to be used at any given point, and no code has to be written to deal
42# with coming in and out of scopes--it falls automatically out from the hint
43# handling
44
45$locale::hint_bits = 0x4;
46$locale::not_chars_hint_bits = 0x10;
47
48sub import {
49    shift;  # should be 'locale'; not checked
50
51    my $found_not_chars = 0;
52    while (defined (my $arg = shift)) {
53        if ($arg eq ":not_characters") {
54            $^H |= $locale::not_chars_hint_bits;
55
56            # This form of the pragma overrides the other
57            $^H &= ~$locale::hint_bits;
58            $found_not_chars = 1;
59        }
60        else {
61            require Carp;
62            Carp::croak("Unknown parameter '$arg' to 'use locale'");
63        }
64    }
65
66    # Use the plain form if not doing the :not_characters one.
67    $^H |= $locale::hint_bits unless $found_not_chars;
68}
69
70sub unimport {
71    $^H &= ~($locale::hint_bits|$locale::not_chars_hint_bits);
72}
73
741;
75