use num::{
    i32, u32, u16, u8
}

type Elf32_Addr, Elf32_Half, Elf32_Off, Elf32_Sword, Elf32_Word, UChar = u32, u16, u32, i32, u32, u8;

let <T> Option<T> = type Some(T) | None;
// is equivalent to
enum Option<T> {
    Some(T),
    None
};