phashmap_inst_coherence.lean:12:53-12:54: error: application type mismatch
  m.find?
argument
  m
has type
  @PersistentHashMap Nat Nat instBEqNat instHashableNat : Type
but is expected to have type
  @PersistentHashMap Nat Nat instBEqNat natDiffHash : Type
phashmap_inst_coherence.lean:12:0-12:56: error: cannot evaluate expression that depends on the `sorry` axiom.
Use `#eval!` to evaluate nevertheless (which may cause lean to crash).