Macro macroex::bail

macro_rules! bail {
    (call_site, $expr: expr) => { ... };
    (call_site, $string: literal $(,$expr: expr)* $(,)?) => { ... };
    ($span: expr, $expr: expr) => { ... };
    ($span: expr, $string: literal $(,$expr: expr)* $(,)?) => { ... };
}

Creates and returns a formatted custom macroex::Error, similar to anyhow::bail!.