Goal:
  
  A : Type
  P : nat → A → A → Type
  i : nat
  hd : A
  hd' : A
  tl : list A
  p : P i hd hd'
  idx3 : nat
  idx4 : list A
  idx2 : list A
  b : OnOne2i P idx3 idx4 idx2
  ============================
   (let H := CoreTactics.block in
    NoConfusion_OnOne2i A P
      {|
        pr1 := {| pr1 := i; pr2 := {| pr1 := hd :: tl; pr2 := hd' :: tl |} |};
        pr2 := OnOne2i_hd P i hd hd' tl p
      |}
      {|
        pr1 := {| pr1 := idx3; pr2 := {| pr1 := idx4; pr2 := idx2 |} |};
        pr2 := b
      |}
    → let H0 := CoreTactics.block in
      {|
        pr1 := {| pr1 := i; pr2 := {| pr1 := hd :: tl; pr2 := hd' :: tl |} |};
        pr2 := OnOne2i_hd P i hd hd' tl p
      |} =
      {|
        pr1 := {| pr1 := idx3; pr2 := {| pr1 := idx4; pr2 := idx2 |} |};
        pr2 := b
      |})


DEBUG:Going to execute:
destruct p || (case p; clear p)
Level 6: evaluation of term
raised the exception
Backtrace:


Could not find an instance for "DepElim.DependentEliminationPackage
                                  (OnOne2i P idx3 idx4 idx2)"
in
environment:
A : Type
P : nat → A → A → Type
i : nat
hd, hd' : A
tl : list A
p : P i hd hd'
idx3 : nat
idx4, idx2 : list A
b : OnOne2i P idx3 idx4 idx2


Level 5: Backtrace:


Could not find an instance for "DepElim.DependentEliminationPackage
                                  (OnOne2i P idx3 idx4 idx2)"
in
environment:
A : Type
P : nat → A → A → Type
i : nat
hd, hd' : A
tl : list A
p : P i hd hd'
idx3 : nat
idx4, idx2 : list A
b : OnOne2i P idx3 idx4 idx2

Level 4: Backtrace:


Could not find an instance for "DepElim.DependentEliminationPackage
                                  (OnOne2i P idx3 idx4 idx2)"
in
environment:
A : Type
P : nat → A → A → Type
i : nat
hd, hd' : A
tl : list A
p : P i hd hd'
idx3 : nat
idx4, idx2 : list A
b : OnOne2i P idx3 idx4 idx2

Level 4: evaluation
raised the exception
Backtrace:


Could not find an instance for "DepElim.DependentEliminationPackage
                                  (OnOne2i P idx3 idx4 idx2)"
in
environment:
A : Type
P : nat → A → A → Type
i : nat
hd, hd' : A
tl : list A
p : P i hd hd'
idx3 : nat
idx4, idx2 : list A
b : OnOne2i P idx3 idx4 idx2


Level 4: Backtrace:


Could not find an instance for "DepElim.DependentEliminationPackage
                                  (OnOne2i P idx3 idx4 idx2)"
in
environment:
A : Type
P : nat → A → A → Type
i : nat
hd, hd' : A
tl : list A
p : P i hd hd'
idx3 : nat
idx4, idx2 : list A
b : OnOne2i P idx3 idx4 idx2

Level 4: Backtrace:


Could not find an instance for "DepElim.DependentEliminationPackage
                                  (OnOne2i P idx3 idx4 idx2)"
in
environment:
A : Type
P : nat → A → A → Type
i : nat
hd, hd' : A
tl : list A
p : P i hd hd'
idx3 : nat
idx4, idx2 : list A
b : OnOne2i P idx3 idx4 idx2

Level 3: Backtrace:


Could not find an instance for "DepElim.DependentEliminationPackage
                                  (OnOne2i P idx3 idx4 idx2)"
in
environment:
A : Type
P : nat → A → A → Type
i : nat
hd, hd' : A
tl : list A
p : P i hd hd'
idx3 : nat
idx4, idx2 : list A
b : OnOne2i P idx3 idx4 idx2

Level 3: evaluation
raised the exception
Backtrace:


Could not find an instance for "DepElim.DependentEliminationPackage
                                  (OnOne2i P idx3 idx4 idx2)"
in
environment:
A : Type
P : nat → A → A → Type
i : nat
hd, hd' : A
tl : list A
p : P i hd hd'
idx3 : nat
idx4, idx2 : list A
b : OnOne2i P idx3 idx4 idx2


Level 3: Backtrace:


Could not find an instance for "DepElim.DependentEliminationPackage
                                  (OnOne2i P idx3 idx4 idx2)"
in
environment:
A : Type
P : nat → A → A → Type
i : nat
hd, hd' : A
tl : list A
p : P i hd hd'
idx3 : nat
idx4, idx2 : list A
b : OnOne2i P idx3 idx4 idx2

Level 2: Backtrace:


Could not find an instance for "DepElim.DependentEliminationPackage
                                  (OnOne2i P idx3 idx4 idx2)"
in
environment:
A : Type
P : nat → A → A → Type
i : nat
hd, hd' : A
tl : list A
p : P i hd hd'
idx3 : nat
idx4, idx2 : list A
b : OnOne2i P idx3 idx4 idx2