use strict;

my $light = Flashlight->new();
my %menu  = (
   1 => ['Turn On',      sub { $light->turn_on }],
   2 => ['Turn Off',     sub { $light->turn_off }],
   3 => ['Toggle',       sub { $light->toggle }],
   4 => ['Flash',        sub { print flash($light),"\n" }],
   5 => ['Change Level', sub { change_level($light) }],
   6 => ['Status',       sub { print $light->to_string }],
   7 => ['Exit',         sub { exit }],
);

while(1) {
   print menu();
   chomp(my $choice = <>);
   last if $choice =~ /^(exit|q|end|x|quit)/i;
   next unless exists $menu{$choice};
   &{$menu{$choice}->[1]};
}

sub menu {
   my $string;
   for (sort keys %menu) {
      $string .= sprintf ("%d) %s\n",$_,$menu{$_}->[0]);
   }
   return $string . 'Enter choice:';
}

sub flash {
   my $ref = shift;
   return $ref->is_on
      ? "The flashlight is on already."
      : "A flash of light beams through the air!"
}

sub change_level {
   my $ref = shift;
   print "Enter Level: ";
   chomp (my $lvl=<>);
   $ref->level($lvl);
   print "Power is at ", $ref->level, "\n";

}

###############################################

package Flashlight;

# constructor
sub new {
   my $class = shift;
   my $power = shift || 0;
   my $level = shift || 0;
   my $self  = {
      level => $level,
      power => $power,
   };
   return bless $self, $class;
}

# set method
sub turn_on {
   my $self = shift;
   $self->{'power'} = 1;
}

# set method
sub turn_off {
   my $self = shift;
   $self->{'power'} = 0;
}

# set method
sub toggle {
   my $self = shift;
   $self->{'power'} = ! $self->{'power'};
}

# get or set method
sub level {
   my $self  = shift;
   my $level = shift;
   return $self->{'level'} unless $level;
   $self->{'level'} = $level;
}

# get method
sub is_on {
   my $self = shift;
   return $self->{'power'};
}

# get method
sub to_string {
   my $self = shift;
   my $string;
   while (my($k,$v) = each %$self) {
      $string .= "$k => " . ($v || 0) . "\n";
   }
   return $string;
}
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jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)