# failure::ensure - Rust
API documentation for the Rust `ensure` macro in crate `failure`.
Keywords: rust, rustlang, rust-lang, ensure

# Macro failure::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.

Similar to `assert!`, `ensure!` takes a condition and exits the function if the condition fails. Unlike `assert!`, `ensure!` returns an `Error`, it does not panic.

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