Failed to solve the following constraints:
  _24 := λ x y → refl [blocked on problem 31]
  [31, 35] _23 = f _23 : o
Unsolved metas at the following locations:
  JasonReedPruning.agda:23,11-12
  JasonReedPruning.agda:21,11-12
  JasonReedPruning.agda:26,19-23
