Comparing two expressions

public function compare(Node|Pool $first, Node|Pool $second, RoundingMode $rounding = RoundingMode::NegativeInfinity): Versus

Two expressions rolled against each other, independently — an attack against a defence, 1d20+5 against 2d10+4:

$versus = $probabilities->compare($dice->parse('1d20+5'), $dice->parse('2d10+4'));

(string) $versus->first;   // "1000/2000": the first is higher
(string) $versus->tie;     // "100/2000": both are equal
(string) $versus->second;  // "900/2000": the second is higher

The three probabilities are exact fractions over the product of both totals, and add up to one. A Versus keeps both distributions, firstDistribution and secondDistribution. It is estimated when either is: isEstimated(), and margin() adds both margins. remaining() is the probability that an explosion was cut at its depth in either.

A Versus can also be built from two distributions already computed: new Versus($first, $second).