#[derive(Debug)]
struct Relation {
    expr: Expression,
    operator: Operator,
    range_list: Vec<RangeListItem>,
}

#[derive(Debug)]
struct Operator(char);

#[derive(Debug)]
struct Expression {
    operand: Operand,
    operation: Option<Operation>
}

#[derive(Debug)]
struct Operation {
    operation_type: OperationType,
    value: Value
}

#[derive(Debug)]
enum OperationType {
    MOD,
    PERCENT,
}

#[derive(Debug)]
struct Operand(char);

#[derive(Debug)]
enum RangeListItem{
    Range(Range),
    Value(Value),
}

#[derive(Debug)]
struct Value(usize);

#[derive(Debug)]
struct Range {
    from: Value,
    to: Value
}

fn main() {
    let cond = Relation {
        expr: Expression {
            operand: Operand('i'),
            operation: None,
        },
        operator: Operator('='),
        range_list: vec![
            RangeListItem::Value(Value(1)),
        ],
    };
    println!("{:#?}", cond);
}