sub toggle {
  my @states = @_;
  my $index = 0;

  return sub {
    return $states[ $index++ % ( scalar @states ) ];
  }
}

##</code><code>##

my $t = &toggle qw( alfa beta gamma );
print &$t(), "\n" foreach ( 1 .. 20 );

##</code><code>##

sub curry {
    my ( $fnc, @arguments ) = @_;

    return sub {
        return &$fnc( @arguments, @_ );
    }
}

##</code><code>##

sub echo {
    return join( " ", @_ );
}

##</code><code>##

my $boss = &curry( \&echo, "My", "boss:" );
my $friend = &curry( \&echo, "Johnny:" );

print &$boss qw( has pointy hair ), "\n"; # "My boss: has pointy hair
print &$friend qw( likes rock and roll ), "\n"; # etc.