Function resolve_prelude 

pub fn resolve_prelude(
    expr: &mut Expr,
    prelude: &[Text],
) -> Result<(), ParseError>

Resolve expr against a named outer prelude (insertion order): a reference to prelude[i] becomes the index i of the root frame — reached directly at the top level, or through a lambda’s capture list from inside one — and any name neither in scope nor in prelude is UnboundName. Like resolve_open but the root frame is fixed and complete (no auto-bind). Used by elly::parse_preluded, whose caller supplies the prelude values in that same order.