pub fn select_first<T, M, R>(
_: &T,
rs: &mut dyn Iterator<Item = (&R, Update<T, M>)>,
) -> Option<Update<T, M>>where
T: Uniplate,
R: Rule<T, M>,Expand description
Returns the first available Update if there is one, otherwise returns None.
This is a good default selection strategy, especially when you expect only one possible rule to apply to any one term.
See the module-level documentation for more information.