arithmetic-eval 0.3.0

Simple interpreter for arithmetic expressions.
Documentation 
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//! DSA signatures on a prime-order cyclic group.

dbg(GEN, ORDER);

gen = || {
    sk = rand_scalar();
    #{ sk, pk: GEN ^ sk }
};

sign = |message, sk| {
    k = rand_scalar();
    r = (GEN ^ k).to_scalar();
    s = (hash_to_scalar(message) + sk * r) / k;
    #{ r, s }
};

verify = |{ r, s }, message, pk| {
    (u1, u2) = (hash_to_scalar(message) / s, r / s);
    (GEN ^ u1 * pk ^ u2).to_scalar() == r
};

// Test!
{ sk, pk } = gen();
{ pk: other_pk } = gen();

5.while(|i| i != 0, |i| {
    message = rand_scalar();
    dbg(message);
    signature = message.sign(sk);
    dbg(signature);

    assert(signature.verify(message, pk));
    assert(!signature.verify(message, other_pk));
    assert(!signature.verify(rand_scalar(), pk));

    i - 1
});