Goal:
    A : Type  R : ReflectEq A  x : A  y : A  Heq_anonymous : true = (x == y)
  ============================
   (x = y)


DEBUG:Going to execute:
<coq-core.plugins.ltac::unify@0> $1 $2
DEBUG LTAC Evaluated term: Type
DEBUG LTAC Evaluated term: (true = (x == y))