Macro error_tools::protected::return_err

macro_rules! return_err {
    ( $msg : expr ) => { ... };
    ( $msg : expr, $( $arg : expr ),+ $(,)? ) => { ... };
}

Macro to return an Err( error ) generating error descriptor.

Basic use-case.

fn f1() -> Result< (), BasicError >
{
  return_err!( "No attr" );
}