anchor.diff:             :v-casts-to-p
              :v-casts-to
              :find-mutual-cast-type
  +           :name
   
              ;;type functions
              :type-specp
  
positive.code:            :v-slots
             :v-true-type
  
             ;;types
             :add-alternate-type-name
             :resolve-name-from-alternative
             :v-type
             :v-stemcell
             :v-array
  
negative.code:            :v-defun
             :v-defmacro
             :v-define-compiler-macro
             :def-metadata-infer
             :def-metadata-kind
             :def-shadow-type-constructor
             :v-deftype
             :add-external-function
             :add-equivalent-name
  
  