RosettaCodeData/Task/First-class-environments/Perl/first-class-environments.pl

41 lines
818 B
Perl

use strict;
use warnings;
use Safe;
sub hail_next {
my $n = shift;
return 1 if $n == 1;
return $n * 3 + 1 if $n % 2;
$n / 2;
};
my @enviornments;
for my $initial ( 1..12 ) {
my $env = Safe->new;
${ $env->varglob('value') } = $initial;
${ $env->varglob('count') } = 0;
$env->share('&hail_next');
$env->reval(q{
sub task {
return if $value == 1;
$value = hail_next( $value );
++$count;
}
});
push @enviornments, $env;
}
my @value_refs = map $_->varglob('value'), @enviornments;
my @tasks = map $_->varglob('task'), @enviornments;
while( grep { $$_ != 1 } @value_refs ) {
printf "%4s", $$_ for @value_refs;
print "\n";
$_->() for @tasks;
}
print "Counts\n";
printf "%4s", ${$_->varglob('count')} for @enviornments;
print "\n";