gistfile1.pl

sub env_filter (&) {                                                                         
    my $code = shift;                                                                        
    sub {                                                                                    
        my $app = shift;                                                                     
        sub {                                                                                
            my $env = shift;                                                                 
            $code->($env);                                                                   
            return $app->($env);                                                             
        };                                                                                   
    }                                                                                        
}                                                                                            
                                                                                             
sub res_filter (&) {                                                                         
    my $code = shift;                                                                        
                                                                                             
    sub {                                                                                    
        my $app = shift;                                                                     
        sub { Plack::Util::response_cb($app->(shift), $code) };                              
    }                                                                                        
}