allValuations.stlx

// p is a set of propostional variables.  This functions computes the set
// of all propositional valuations that can be build with the variables
// of p.
allValuations := procedure(p) {
    if (p == {}) {
        return { {} };
    }
    x := arb(p);
  	p -= { x };
    a := allValuations(p);
    return { { [x, true] } + i : i in a } + { { [x, false] } + i : i in a };
};

test := procedure(p) {
    print("testing " + p);
    for (i in allValuations(p)) { 
        print(i); 
    }
};

run := procedure(n) {
    for (k in [1 .. n]) {
        print("n = " + k + ":");
        p := { "x" + i : i in [1 .. k] };
        test(p);
    }
};

run(5);