Implement typeclasses analogous to Fractional and AsFractional for discardable fractions
I think it would make sense to have a library analogous to fractional for discardable fractions. I think it needs to say Φ (p ⋅ q) ⊣⊢ Φ p ∗ Φ q
like for fractions (using dfrac composition) and also perhaps Persistent (Φ DfracDiscarded)
.