type assumption =
  | ADDS_TO_1
  | ADDS_TO_CORRECT_PROBABILITY;
type assumptions = {
  continuous: assumption,
  discrete: assumption,
  discreteProbabilityMass: option(float),
};
let build = (~continuous, ~discrete, ~assumptions) =>
  switch (assumptions) {
  | {
      continuous: ADDS_TO_CORRECT_PROBABILITY,
      discrete: ADDS_TO_CORRECT_PROBABILITY,
      discreteProbabilityMass: Some(r),
    } =>
    // TODO: Fix this, it's wrong :(
    Some(
      Shape.Mixed.make(
        ~continuous,
        ~discrete,
        ~discreteProbabilityMassFraction=r,
      ),
    )
  | {
      continuous: ADDS_TO_1,
      discrete: ADDS_TO_1,
      discreteProbabilityMass: Some(r),
    } =>
    Some(
      Shape.Mixed.make(
        ~continuous,
        ~discrete,
        ~discreteProbabilityMassFraction=r,
      ),
    )
  | {
      continuous: ADDS_TO_1,
      discrete: ADDS_TO_1,
      discreteProbabilityMass: None,
    } =>
    None
  | {
      continuous: ADDS_TO_CORRECT_PROBABILITY,
      discrete: ADDS_TO_1,
      discreteProbabilityMass: None,
    } =>
    None
  | {
      continuous: ADDS_TO_1,
      discrete: ADDS_TO_CORRECT_PROBABILITY,
      discreteProbabilityMass: None,
    } =>
    let discreteProbabilityMassFraction = Shape.Discrete.ySum(discrete);
    let discrete = Shape.Discrete.scaleYToTotal(1.0, discrete);
    Some(
      Shape.Mixed.make(
        ~continuous,
        ~discrete,
        ~discreteProbabilityMassFraction,
      ),
    );
  | _ => None
  };