# Macro failure::format_err [−] [src]

    macro_rules! format_err {
        ($($arg:tt)*) => { ... };
    }

Constructs an `Error` using the standard string interpolation syntax.

    #[macro_use] extern crate failure;

    fn main() {
        let code = 101;
        let err = format_err!("Error code: {}", code);
    }

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