#[derive(Debug, Clone)]
pub enum Token {
    Negation,
    Conjunction,
    Disjunction,
    ExclusiveDisjunction,
    MaterialCondition,
    LogicalEquivalence
}

#[derive(Debug, Clone)]
pub enum Node<T> {
    Leaf(T),
    Unary {
        operator: Token,
        operand: Box<Node<T>>
    },
    Binary {
        operator: Token,
        lhs: Box<Node<T>>,
        rhs: Box<Node<T>>,
    },
}

pub fn add_unary_node<T>(stack: &mut Vec<Node<T>>, token: Token) {
    let operand = Box::new(stack.pop().unwrap());
    stack.push(Node::Unary {
        operator: token,
        operand,
    });
}

pub fn add_binary_node<T>(stack: &mut Vec<Node<T>>, token: Token) {
    let lhs = Box::new(stack.pop().unwrap());
    let rhs = Box::new(stack.pop().unwrap());
    stack.push(Node::Binary {
        operator: token,
        lhs,
        rhs
    });
}