# core::writeln!1.0.0 [−] [src]

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

1.0.0

Use the `format!` syntax to write data into a buffer, appending a newline. On all platforms, the newline is the LINE FEED character (`\n`/`U+000A`) alone (no additional CARRIAGE RETURN (`\r`/`U+000D`).

This macro is typically used with a buffer of `&mut` `Write`.

See `std::fmt` for more information on format syntax.

# Examples

fn main() { use std::io::Write; let mut w = Vec::new(); writeln!(&mut w, "test").unwrap(); writeln!(&mut w, "formatted {}", "arguments").unwrap(); assert_eq!(&w[..], "test\nformatted arguments\n".as_bytes()); }

    use std::io::Write;

    let mut w = Vec::new();
    writeln!(&mut w, "test").unwrap();
    writeln!(&mut w, "formatted {}", "arguments").unwrap();

    assert_eq!(&w[..], "test\nformatted arguments\n".as_bytes());

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