From f61148b2e4c7608c5d7cbbf08ddfcbfd9c5afebf Mon Sep 17 00:00:00 2001 From: Tom Wyant Date: Tue, 11 Jan 2022 21:19:47 -0500 Subject: [PATCH] Convert 21_Calendar to Perl. This is pretty much a complete rewrite. It displays the current year, but that can be changed by specifying the desired year on the command line. It MAY even be sensitive enough to locale to produce output in languages other than English. --- 21_Calendar/perl/README.md | 10 +++ 21_Calendar/perl/calendar.pl | 130 +++++++++++++++++++++++++++++++++++ 2 files changed, 140 insertions(+) create mode 100755 21_Calendar/perl/calendar.pl diff --git a/21_Calendar/perl/README.md b/21_Calendar/perl/README.md index e69c8b81..043be194 100644 --- a/21_Calendar/perl/README.md +++ b/21_Calendar/perl/README.md @@ -1,3 +1,13 @@ Original source downloaded [from Vintage Basic](http://www.vintage-basic.net/games.html) Conversion to [Perl](https://www.perl.org/) + +Actually, this is not so much a port as a complete rewrite, making use of +Perl's Posix time functionality. The calendar is for the current year (not +1979), but you can get another year by specifying it on the command line, e.g. + + `perl 21_Calendar/perl/calendar.pl 2001` + +It *may* even produce output in languages other than English. But the +leftmost column will still be Sunday, even in locales where it is +typically Monday. diff --git a/21_Calendar/perl/calendar.pl b/21_Calendar/perl/calendar.pl new file mode 100755 index 00000000..96ba387b --- /dev/null +++ b/21_Calendar/perl/calendar.pl @@ -0,0 +1,130 @@ +#!/usr/bin/env perl + +use 5.010; # To get 'state' and 'say' + +use strict; # Require explicit declaration of variables +use warnings; # Enable optional compiler warnings + +use English; # Use more friendly names for Perl's magic variables +use POSIX qw{ strftime }; +use Term::ReadLine; # Prompt and return user input +use Time::Local (); + +BEGIN { + *time_gm = + Time::Local->can( 'timegm_modern' ) || + Time::Local->can( 'timegm' ); +} + +our $VERSION = '0.000_01'; + +use constant COLUMN_WIDTH => 6; +use constant SECONDS_PER_DAY => 86400; + +binmode STDOUT, ':encoding(utf-8)'; + +my $year = @ARGV ? $ARGV[0] : ( localtime )[5] + 1900; +my $is_leap_year = is_leap_year( $year ); +my $year_len = 365 + $is_leap_year; +print <<'EOD'; + CALENDAR + Creative Computing Morristown, New Jersey + + +EOD + +my @mon_len = ( 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 ); +$mon_len[1] += $is_leap_year; + +foreach my $month ( 0 .. 11 ) { + my $epoch = time_gm( 0, 0, 0, 1, $month, $year ); + my @start_time = gmtime( $epoch ); + my ( $week_day, $year_day ) = @start_time[ 6, 7 ]; + my $label = strftime( '%B %Y', @start_time ); + $label .= ' ' x ( ( 14 - length $label ) / 2 ); + printf "\n** %3d ****** %14s ****** %3d **\n", + $year_day, $label, $year_len - $year_day; + { + my $day = 1 + ( 7 - $week_day ) % 7; + foreach my $wd ( 0 .. 6 ) { + my $ep = time_gm( 0, 0, 0, $day + $wd, $month, $year ); + printf '%*s', COLUMN_WIDTH, strftime( '%a', gmtime $ep ); + } + print "\n"; + } + say '*' x ( COLUMN_WIDTH * 7 ); + print ' ' x ( COLUMN_WIDTH * $week_day ); + my $month_day = 1; + while ( $week_day < 7 ) { + printf '%*d', COLUMN_WIDTH, $month_day++; + $week_day++; + } + print "\n"; + $week_day = 0; + while ( $month_day <= $mon_len[$month] ) { + printf '%*d', COLUMN_WIDTH, $month_day++; + $week_day++; + unless ( $week_day % 7 ) { + print "\n"; + $week_day = 0; + } + } + print "\n" if $week_day; + +} + +sub is_leap_year { + my ( $year ) = 1; + return 0 if $year % 4; + return 1 if $year % 100; + return 0 if $year % 400; + return 1; +} + +__END__ + +=head1 TITLE + +calendar - Play the game 'Calendar' from Basic Computer Games + +=head1 SYNOPSIS + + calendar.pl + +=head1 DETAILS + +This Perl script is a port of calendar, which is the 21st +entry in Basic Computer Games. + +Actually, it is not so much a port as a complete rewrite, making use of +Perl's Posix time functionality. The calendar is for the current year +(not 1979), but you can get another year by specifying it on the command +line, e.g. + + perl 21_Calendar/perl/calendar.pl 2001 + +It B even produce output in languages other than English. But the +leftmost column will still be Sunday, even in locales where it is +typically Monday. + +=head1 PORTED BY + +Thomas R. Wyant, III F + +=head1 COPYRIGHT AND LICENSE + +Copyright (C) 2022 by Thomas R. Wyant, III + +This program is free software; you can redistribute it and/or modify it +under the same terms as Perl 5.10.0. For more details, see the Artistic +License 1.0 at +L, and/or the +Gnu GPL at L. + +This program is distributed in the hope that it will be useful, but +without any warranty; without even the implied warranty of +merchantability or fitness for a particular purpose. + +=cut + +# ex: set expandtab tabstop=4 textwidth=72 :