anchor.diff:    (completion-suggestions-for-input input-string cursor-position *shell-readtable*))
   
   (defun logging-token-sequence (stream)
  -  "Return an iterator that produces the tokens found in `stream'.
  +  "Return a sequence that produces the tokens found in `stream'.
   
   Tokens are read using `*shell-readtable*'."
     (lazy-map (tokens-in-stream-symbolic-readtable stream '*shell-readtable*)
  
positive.code:               (startup-file (probe-file "~/.shclrc.lisp")))
            (when startup-file
              (load startup-file))
            (handler-bind
                ((parse-failure
                  (lambda (e)
                    (when-let ((restart (find-restart 'ignore-command)))
                      (format *error-output* "Parse error: ~A~%" e)
                      (invoke-restart restart)))))
              (let ((result (truthy-exit-info)))
                (handler-case
                    (do-iterator (values (main-iterator stream :history h))
                      (if (exit-info-p (car values))
                          (setf result (car values))
                          (warn "Got non-exit-info result: ~A" values)))
                  (exit-condition (e)
                    (setf result (exit-condition-exit-info e))))
                (exit (exit-info-code result)))))))))
  
negative.code:   (:use
     :common-lisp :trivial-gray-streams :shcl/core/lexer :shcl/core/shell-grammar
     :shcl/core/utility :shcl/core/evaluate
     :shcl/core/lisp-interpolation :shcl/core/dispatch-table)
    (:import-from :shcl/core/sequence
     #:lazy-map #:do-while-popf #:do-sequence #:wrap-with #:cache-impure)
    (:import-from :shcl/core/command #:define-builtin)
    (:import-from :shcl/core/shell-lambda
     #:handle-command-errors #:with-parsed-arguments)
    (:import-from :shcl/core/posix #:exit)
    (:import-from :shcl/core/command #:exit-condition #:exit-condition-exit-info)
    (:import-from :shcl/core/exit-info
     #:truthy-exit-info #:exit-info-code #:exit-info-p #:falsey-exit-info)
    (:import-from :shcl/core/environment #:env)
    (:import-from :shcl/shell/directory)
    (:import-from :shcl/shell/builtins)
  