Function get_dictionary_property 

pub unsafe fn get_dictionary_property(
    cx: *mut JSContext,
    object: HandleObject<'_>,
    property: &str,
    rval: MutableHandleValue<'_>,
    _can_gc: CanGc,
) -> Result<bool, ()>

Get the property with name property from object. Returns Err(()) on JSAPI failure (there is a pending exception), and Ok(false) if there was no property with the given name.

Safety

cx must point to a valid, non-null JSContext.