pub struct String;

pub struct Either<L, R> {
  is_right: bool,
  value: L | R,
}

mod io {

  pub type Result<T> = Either<Error, T>;

  pub foreign "JS" fn print(message: String) {
    process.stdout.write(message);
  }

  pub trait Read {
    fn read(self, count: usize, target: Vec<u8>) -> Result<usize>;
  }

  impl Read for File {

    foreign "JS" fn read(self, count, target) -> Result<usize> {

      import * as fs from "fs"

      try {
        return Ok(fs.readSync(self.fd, target, 0, count, null));
      } catch (e) {
        return Err(e.code);
      }

    }

  }

}

print("Hello, world!");