NAME

Raku port of Perl's localtime / gmtime built-ins

SYNOPSIS

use P5localtime;

#     0    1    2     3     4    5     6     7     8
my ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) = localtime(time);
say localtime(Scalar, time);

my ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday) = gmtime(time);
say gmtime(Scalar, time);

DESCRIPTION

This module tries to mimic the behaviour of Perl's localtime and gmtime built-ins as closely as possible in the Raku Programmming Language.

ORIGINAL PERL 5 DOCUMENTATION

localtime EXPR
localtime
        Converts a time as returned by the time function to a 9-element
        list with the time analyzed for the local time zone. Typically
        used as follows:

            #  0    1    2     3     4    5     6     7     8
            ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) =
                                                        localtime(time);

        All list elements are numeric and come straight out of the C
        `struct tm'. $sec, $min, and $hour are the seconds, minutes, and
        hours of the specified time.

        $mday is the day of the month and $mon the month in the range
        0..11, with 0 indicating January and 11 indicating December. This
        makes it easy to get a month name from a list:

            my @abbr = qw(Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec);
            print "$abbr[$mon] $mday";
            # $mon=9, $mday=18 gives "Oct 18"

        $year contains the number of years since 1900. To get a 4-digit
        year write:

            $year += 1900;

        To get the last two digits of the year (e.g., "01" in 2001) do:

            $year = sprintf("%02d", $year % 100);

        $wday is the day of the week, with 0 indicating Sunday and 3
        indicating Wednesday. $yday is the day of the year, in the range
        0..364 (or 0..365 in leap years.)

        $isdst is true if the specified time occurs during Daylight Saving
        Time, false otherwise.

        If EXPR is omitted, "localtime()" uses the current time (as
        returned by time(3)).

        In scalar context, "localtime()" returns the ctime(3) value:

            $now_string = localtime;  # e.g., "Thu Oct 13 04:54:34 1994"

        The format of this scalar value is not locale-dependent but built
        into Perl. For GMT instead of local time use the "gmtime" builtin.
        See also the "Time::Local" module (for converting seconds,
        minutes, hours, and such back to the integer value returned by
        time()), and the POSIX module's strftime(3) and mktime(3)
        functions.

        To get somewhat similar but locale-dependent date strings, set up
        your locale environment variables appropriately (please see
        perllocale) and try for example:

            use POSIX qw(strftime);
            $now_string = strftime "%a %b %e %H:%M:%S %Y", localtime;
            # or for GMT formatted appropriately for your locale:
            $now_string = strftime "%a %b %e %H:%M:%S %Y", gmtime;

        Note that the %a and %b, the short forms of the day of the week
        and the month of the year, may not necessarily be three characters
        wide.

        The Time::gmtime and Time::localtime modules provide a convenient,
        by-name access mechanism to the gmtime() and localtime()
        functions, respectively.

        For a comprehensive date and time representation look at the
        DateTime module on CPAN.

        Portability issues: "localtime" in perlport.

gmtime EXPR
gmtime  Works just like "localtime" but the returned values are localized
        for the standard Greenwich time zone.

        Note: When called in list context, $isdst, the last value returned
        by gmtime, is always 0. There is no Daylight Saving Time in GMT.

        Portability issues: "gmtime" in perlport.

PORTING CAVEATS

Mimicking scalar context

Since Raku does not have a concept of scalar context, this must be mimiced by passing the Scalar type as the first positional parameter.

The implementation actually also returns the offset in GMT in seconds as element number 9, and the name of the timezone as element number 10, if supported by the OS.

Depends on POSIX semantics

This module depends on the availability of POSIX semantics. This is generally not available on Windows, so this module will probably not work on Windows.

AUTHOR

Elizabeth Mattijsen [email protected]

Source can be located at: https://github.com/lizmat/P5localtime . Comments and Pull Requests are welcome.

ACKNOWLEDGEMENTS

JJ Merelo, Jan-Olof Hendig, Tobias Leich, Timo Paulssen and Christoph (on StackOverflow) for support in getting this to work.

COPYRIGHT AND LICENSE

Copyright 2018, 2019, 2020, 2021 Elizabeth Mattijsen

Re-imagined from Perl as part of the CPAN Butterfly Plan.

This library is free software; you can redistribute it and/or modify it under the Artistic License 2.0.