| /// A simple static assertion macro. |
| #[macro_export] |
| #[allow_internal_unstable(type_ascription)] |
| macro_rules! static_assert { |
| ($test:expr) => { |
| // Use the bool to access an array such that if the bool is false, the access |
| // is out-of-bounds. |
| #[allow(dead_code)] |
| const _: () = [()][!($test: bool) as usize]; |
| }; |
| } |
| |
| /// Type size assertion. The first argument is a type and the second argument is its expected size. |
| #[macro_export] |
| macro_rules! static_assert_size { |
| ($ty:ty, $size:expr) => { |
| const _: [(); $size] = [(); ::std::mem::size_of::<$ty>()]; |
| }; |
| } |
| |
| #[macro_export] |
| macro_rules! enum_from_u32 { |
| ($(#[$attr:meta])* pub enum $name:ident { |
| $($variant:ident = $e:expr,)* |
| }) => { |
| $(#[$attr])* |
| pub enum $name { |
| $($variant = $e),* |
| } |
| |
| impl $name { |
| pub fn from_u32(u: u32) -> Option<$name> { |
| $(if u == $name::$variant as u32 { |
| return Some($name::$variant) |
| })* |
| None |
| } |
| } |
| }; |
| ($(#[$attr:meta])* pub enum $name:ident { |
| $($variant:ident,)* |
| }) => { |
| $(#[$attr])* |
| pub enum $name { |
| $($variant,)* |
| } |
| |
| impl $name { |
| pub fn from_u32(u: u32) -> Option<$name> { |
| $(if u == $name::$variant as u32 { |
| return Some($name::$variant) |
| })* |
| None |
| } |
| } |
| } |
| } |