#[cfg(feature = "verbose")]
macro_rules! debugln {
($fmt:expr) => (println!($fmt));
($fmt:expr, $($arg:tt)*) => (println!($fmt, $($arg)*));
}
#[cfg(not(feature = "verbose"))]
macro_rules! debugln {
($fmt:expr) => ();
($fmt:expr, $($arg:tt)*) => ();
}