Function funs 

pub fn funs<D: DataT>() -> impl Iterator<Item = Filter<Native<D>>>
where
    for<'a> D::V<'a>: ValT,

Minimal set of filters that are generic over the value type.

Return the minimal set of named filters available in jaq which are implemented as native filters, such as error, path, …

Does not return filters from the standard library, such as map.