(defvar *new-constituent-traits*
  (let ((table (copy-trait-table *default-constituent-traits*)))
    (setf (find-traits #\_ table) (list (find-trait :alphabetic)
                                        (find-trait :decimal-separator))
          (find-traits #\~ table) (list (find-trait :alphabetic)
                                        (find-trait :ratio-marker))
          (find-traits #\⨁ table) (list (find-trait :alphabetic)
                                        (find-trait :plus-sign))
          (find-traits #\: table) (list (find-trait :alphabetic))
          (find-traits #\> table) (list (find-trait :package-marker)))
    table))

(let ((*constituent-trait-table* *new-constituent-traits*))
  (read-from-string "(⨁1_234_567~7_654_321 foo:bar >keyword)"))
;; (1234567/7654321 |FOO:BAR| :KEYWORD)
;; 39