macro_rules! ensure { ($condition:expr) => { ... }; ($condition:expr, $message:literal) => { ... }; ($condition:expr, $fmt:expr, $($arg:tt)*) => { ... }; ($condition:expr, $error:expr) => { ... }; }
Expand description
Check that the given condition holds, otherwise return an error.
The argument can be either:
- a condition, in which case a generic error is logged at the
Unspecified
level. - a condition and a string literal, in which case the provided literal is logged at the
Unspecified
level. - a condition and a format expression, in which case the message is formatted and logged at the
Unspecified
level. - a condition and an
Error
, in which case the given error is logged unchanged.