Propositional logic evaluator.

Supported operators and symbols:

• Not: not, ¬, !, ∼
• And: and, &, &&, ∧
• Or: or, |, ||, ∨
• XOr: xor, ⊕
• Implication: ->, =>, ⇒, →, ⊃
• Biconditional: <->, <=>, ⇔, ↔, iff, xnor
• Logical equivalence: =, ==, eq, ≡
• Not equal: !=, ≠
• parentheses: (), {}, []
• True: 1, true, True
• False: 0, false, False
• Variables: a-z, A-Z

Note: the order of evaluation of operators are: not, and, or, xor, →, ↔, ≡ and ≠. Please use parentheses in order to adjust the operator priorities. incorrect expressions result in wrong tables.

Note: Characters are case sensetive. for example q is not the same as Q.

Example:

• Truth table for P ∨ (Q ∧ R) ≡ (P ∨ Q) ∧ (P ∨ R) or P or (Q and R) == (P or Q) and (P or R)

P	Q	R	(Q ∧ R)	(P ∨ (Q ∧ R))	(P ∨ Q)	(P ∨ R)	((P ∨ Q) ∧ (P ∨ R))	((P ∨ (Q ∧ R)) ≡ ((P ∨ Q) ∧ (P ∨ R)))
true	true	true	true	true	true	true	true	true
true	true	false	false	true	true	true	true	true
true	false	true	false	true	true	true	true	true
true	false	false	false	true	true	true	true	true
false	true	true	true	true	true	true	true	true
false	true	false	false	false	true	false	false	true
false	false	true	false	false	false	true	false	true
false	false	false	false	false	false	false	false	true

• Truth table for (P ∧ (∼ Q)) ⇔ (P ⇒ Q) or (P and (not Q) <-> (P -> Q))

P	Q	¬Q	(P ∧ ¬Q)	(P → Q)	((P ∧ ¬Q) ↔ (P → Q))
true	true	false	false	true	false
true	false	true	true	false	false
false	true	false	false	true	false
false	false	true	false	true	false

• Truth table for not true or not false

P	Q	¬P	¬Q	(¬P ∨ ¬Q)
false	true	true	false	true

How to run

1. install rust. see here for the instructions.
2. run cargo run to run the app.
3. run cargo test to run the tests.

How to use

You can export the truth tables to one of the following formats or print it to terminal.

• csv
• html
• pdf (at the moment, does not support displaying some math characters)

    let s = "(P and not Q) <-> (P -> Q)";//"(P ∧ (∼ Q)) ⇔ (P ⇒ Q)";
    let tokens = Tokens::from_text(s);
    match Evaluator::new(tokens) {
        Ok(evaluator) => {
            match evaluator.evaluate_all() {
                Ok(result) => {
                    print!("{}\n",result);
                    // result.save_to_html("test.html");
                    // result.save_to_csv("test.csv");
                    // result.save_to_pdf("test.pdf");
                },
                Err(error) => {
                    println!("{}",error);
                },
            }
        },
        Err(er) => {
            println!("{}",er);
        },
    }

Or you can evaluate for specific values for P and Q only.

    let s = "(∼ P) ∨ (∼ Q)";
    let tokens = Tokens::from_text(s);
    let evaluator = Evaluator::new(tokens).unwrap();
    let mut values = IndexMap::<char,bool>::new();
    values.insert('P', false);
    values.insert('Q', true);
    let mut result = evaluator.evaluate(&values).unwrap();
    for v in values.iter().rev() {
        result.insert_before(0, (*v.0).into(), *v.1);
    }
    let result = evaluator_result::EvaluatorResult{result:vec![result]};
    println!("{}",result);
    // result.save_to_html("test.html");
    // result.save_to_csv("test.csv");
    // result.save_to_pdf("test.pdf");