Function is_err

pub fn is_err<V, T>(value: V) -> Signal<bool>
where
    V: Into<MaybeSignal<Result<T, ()>>>,
    T: 'static,

Reactive Result::is_err().

Usage

let (example, set_example) = create_signal(
    if js_sys::Math::random() < 0.5 { Ok("Example") } else { Err(()) }
);

let is_error = is_err(example);