Goal:
    A : Type  RA : ReflectEq A  x : list A  y : list A
  ============================
   (reflectProp (x = y) (eqb_list eqb x y))


DEBUG:Going to execute:
match H with
           | H' => fail 2
           | _ => unify X Y; clear H' || clear H
           end
Level 4: Backtrace:

In environment
A : Type
RA : ReflectEq A
x, y : list A
Unable to unify "ReflectEq A" with "list A".
Level 4: Backtrace:

In environment
A : Type
RA : ReflectEq A
x, y : list A
Unable to unify "ReflectEq A" with "list A".
Level 4: Backtrace:

In environment
A : Type
RA : ReflectEq A
x, y : list A
Unable to unify "ReflectEq A" with "list A".
Level 4: Backtrace:

In environment
A : Type
RA : ReflectEq A
x, y : list A
Unable to unify "ReflectEq A" with "list A".
Level 3: Backtrace:

In environment
A : Type
RA : ReflectEq A
x, y : list A
Unable to unify "ReflectEq A" with "list A".