Function host_values 

pub fn host_values(
    spec: &ModelSpec,
    var: &str,
    positions: usize,
    source: &mut dyn WeightSource,
) -> Result<Option<Vec<f64>>>

The values of the host table var names (HostTable::named) for a model of spec: a decode step’s caches of positions rows, or a forward’s one row (position 0). None when var names no table.