Never type
Syntax
NeverType :!
The never type !
is a type with no values, representing the result of
computations that never complete. Expressions of type !
can be coerced into
any other type.
let x: ! = panic!();
// Can be coerced into any type.
let y: u32 = x;
NB. The never type was expected to be stabilized in 1.41, but due
to some last minute regressions detected the stabilization was
temporarily reverted. The !
type can only appear in function return
types presently. See the tracking
issue for more
details.