std::eprintln - Rust
Description: API documentation for the Rust `eprintln` macro in crate `std`.
Keywords: rust, rustlang, rust-lang, eprintln

# Macro std::eprintln 1.19.0 [−] [src]

    macro_rules! eprintln {
        () => { ... };
        ($fmt:expr) => { ... };
        ($fmt:expr, $($arg:tt)*) => { ... };
    }

Macro for printing to the standard error, with a newline.

Equivalent to the `println!` macro, except that output goes to `io::stderr` instead of `io::stdout`. See `println!` for example usage.

Use `eprintln!` only for error and progress messages. Use `println!` instead for the primary output of your program.

# Panics

Panics if writing to `io::stderr` fails.

# Examples

    eprintln!("Error: Could not complete task");Run

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