anchor.diff:      (let* ((*standard-output* stream)
              (*error-output* stream))
         (funcall body))))
  -
  
positive.code:                 "~&Unhandled SERIOUS-CONDITION of type ~A is signaled: ~A~%"
                  (type-of condition)
                  condition)
          (funcall on-problem-func)))))
  
  (defun saving-output (file body)
  
negative.code:                        :if-exists :supersede
                         :if-does-not-exist :create)
      (pprint value out)))
  
  ;;; backtrace printing, copy-pasted form ASDF git at 2013-02-19
  
  (defmacro with-safe-io-syntax ((&key (package :cl)) &body body)
    "Establish safe CL reader options around the evaluation of BODY"
    `(call-with-safe-io-syntax #'(lambda () (let ((*package* (find-package ,package))) ,@body))))
  
  (defun call-with-safe-io-syntax (thunk &key (package :cl))
    (with-standard-io-syntax
      (let ((*package* (find-package package))
            (*read-default-float-format* 'double-float)
            (*print-readably* nil)
            (*read-eval* nil))
        (funcall thunk)))))
  
  (defun raw-print-backtrace (&key (stream *debug-io*) count)
    "Print a backtrace, directly accessing the implementation"
    (declare (ignorable stream count))
    #+abcl
    (let ((*debug-io* stream)) (top-level::backtrace-command count))
    #+allegro
    (let ((*terminal-io* stream)
          (*standard-output* stream)
          (tpl:*zoom-print-circle* *print-circle*)
          (tpl:*zoom-print-level* *print-level*)
          (tpl:*zoom-print-length* *print-length*))
      (tpl:do-command "zoom"
        :from-read-eval-print-loop nil
        :count t
        :all t))
    #+clisp
    (system::print-backtrace :out stream :limit count)
    #+(or clozure mcl)
    (let ((*debug-io* stream))
      (ccl:print-call-history :count count :start-frame-number 1)
      (finish-output stream))
    #+(or cmu scl)
    (let ((debug:*debug-print-level* *print-level*)
          (debug:*debug-print-length* *print-length*))
      (debug:backtrace most-positive-fixnum stream))
    #+ecl
    (si::tpl-backtrace)
    #+lispworks
    (let ((dbg::*debugger-stack*
           (dbg::grab-stack nil :how-many (or count most-positive-fixnum)))
          (*debug-io* stream)
          (dbg:*debug-print-level* *print-level*)
          (dbg:*debug-print-length* *print-length*))
      (dbg:bug-backtrace nil))
    #+sbcl
    (sb-debug:backtrace
     #.(if (find-symbol* "*VERBOSITY*" "SB-DEBUG" nil) :stream '(or count most-positive-fixnum))
     stream))
  
  (defun print-backtrace (&rest keys &key stream count)
    (declare (ignore stream count))
    (with-safe-io-syntax (:package :cl)
      (let ((*print-readably* nil)
            (*print-circle* t)
            (*print-miser-width* 75)
            (*print-length* nil)
            (*print-level* nil)
            (*print-pretty* t))
        (ignore-errors (apply 'raw-print-backtrace keys)))))
  
  ;;; end of backtrace printing
  
  (defun catching-problems (body-func on-problem-func)
    "Runs BODY-FUNC and returns it's result. But if BODY-FUNC causes any
  