Goal:
  
  elt : Type
  bst_dec : forall t : M.Raw.tree elt, {M.Raw.bst t} + {~ M.Raw.bst t}
  t : M.Raw.tree elt
  ============================
   (M.Raw.bst (M.Raw.Leaf elt))


DEBUG:Going to execute:
<coq-core.plugins.ltac::constructor@0>

Goals:

DEBUG:Going to execute:
assumption

Goals:

DEBUG:Going to execute:
fun => <coq-core.plugins.ltac::assumption@0>