# Macro error_chain::ensure [−] [src]

    macro_rules! ensure {
        ($cond:expr, $e:expr) => { ... };
        ($cond:expr, $fmt:expr, $($arg:tt)+) => { ... };
    }

Exits a function early with an error if the condition is not satisfied

The `ensure!` macro is a convenience helper that provides a way to exit a function with an error if the given condition fails.

As an example, `ensure!(condition, "error code: {}", errcode)` is equivalent to

    if !condition {
        bail!("error code: {}", errcode);
    }

See documentation for `bail!` macro for further details.

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