ready_set_boole/src/ast.rs

79 lines
1.8 KiB
Rust

mod tests;
#[derive(Debug, Clone, PartialEq)]
pub enum Token {
Negation,
Conjunction,
Disjunction,
ExclusiveDisjunction,
MaterialCondition,
LogicalEquivalence
}
#[derive(Debug, Clone, PartialEq)]
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 rhs = Box::new(stack.pop().unwrap());
let lhs = Box::new(stack.pop().unwrap());
stack.push(Node::Binary {
operator: token,
lhs,
rhs
});
}
fn bool_to_char(b: bool) -> char {
match b {
false => '0',
true => '1'
}
}
fn token_to_char(token: Token) -> char {
match token {
Token::Negation => '!',
Token::Conjunction =>'&',
Token::Disjunction => '|',
Token::ExclusiveDisjunction => '^',
Token::MaterialCondition => '>',
Token::LogicalEquivalence => '=',
}
}
fn ast_to_formula(ast: Node<bool>) -> String {
let mut str = String::from("");
match ast {
Node::Unary { operator, operand } => {
str.push_str(ast_to_formula(*operand).as_str());
str.push(token_to_char(operator));
},
Node::Binary { operator, lhs, rhs } => {
str.push_str(ast_to_formula(*rhs).as_str());
str.push_str(ast_to_formula(*lhs).as_str());
str.push(token_to_char(operator));
},
Node::Leaf(b) => str.push(bool_to_char(b)),
};
str
}