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#![no_std]
#[macro_export]
macro_rules! switch {
($v:expr; $($a:expr => $b:expr,)* _ => $e:expr $(,)?) => {
match $v {
$(v if v == $a => $b,)*
_ => $e,
}
};
}
#[cfg(test)]
mod tests {
const A: u32 = 1 << 0;
const B: u32 = 1 << 1;
const C: u32 = 1 << 2;
const D: u32 = 1 << 3;
#[test]
fn it_works() {
assert!(switch! { 1; _ => true });
let v = switch! { A | B;
A => false,
B | C => false,
A | B => true,
C | D => {
unreachable!();
},
_ => false,
};
assert!(v);
}
#[test]
fn no_trailing_comma() {
let v = switch! { 1;
1 => true,
_ => false
};
assert!(v);
}
}