Function parse_struct 

pub fn parse_struct<'a>(
    s: &'a SExpr,
    expected_name: &str,
) -> Result<BTreeMap<String, &'a SExpr>, SExprError>

Pull a struct-form list by name, returning its field map.

Errors

Returns SExprError::Shape if the head symbol doesn’t match expected_name or the form isn’t a list of keyword pairs.