Macro ra_ap_stdx::never [−][src]
macro_rules! never { (true $($tt:tt)*) => { ... }; (false $($tt:tt)*) => { ... }; () => { ... }; ($fmt:literal $(, $($arg:tt)*)?) => { ... }; ($cond:expr) => { ... }; ($cond:expr, $fmt:literal $($arg:tt)*) => { ... }; }
Asserts that the condition is never true and returns its actual value.
If the condition is false does nothing and and evaluates to false.
If the condition is true:
- panics if
force
feature ordebug_assertions
are enabled, - logs an error if
log
feature is enabled, - evaluates to true.
Accepts format!
style arguments.
Empty condition is equivalent to false:
ⓘ
never!("oups") ~= unreachable!("oups")