pub fn parse_preluded(src: &str, prelude: &[Text]) -> Result<Expr, Error>Expand description
Parse Elly source into an Expr resolved against a named prelude: names
in the prelude resolve to de Bruijn locals, unknown names are rejected with
ParseError::UnboundName. The prelude is an ordered slice of names
(insertion order) that forms a fixed outer frame below all lambda scopes.
Prefer parse for a whole program without a prelude.