(motive : Lean.Environment × Task (Option Lean.Kernel.Exception) × Dynamic → Sort u_1) →
  (__discr : Lean.Environment × Task (Option Lean.Kernel.Exception) × Dynamic) →
    ((env : Lean.Environment) →
        (exTask : Task (Option Lean.Kernel.Exception)) → (dyn : Dynamic) → motive (env, exTask, dyn)) →
      motive __discr