src/callint.lisp

   1 ;;; Call a Lisp function interactively.
   2
   3 (defvar *prefix-arg* nil
   4   "The value of the prefix argument for the next editing command.
   5 It may be a number, or the symbol `-' for just a minus sign as arg,
   6 or a list whose car is a number for just one or more C-u's
   7 or nil if no argument has been specified.
   8
   9 You cannot examine this variable to find the argument for this command
  10 since it has been set to nil by the time you can look.
  11 Instead, you should use the variable `current-prefix-arg', although
  12 normally commands can get this prefix argument with (interactive \"P\").")
  13
  14 (defvar *last-prefix-arg* nil
  15 "The value of the prefix argument for the previous editing command.
  16 See `prefix-arg' for the meaning of the value.")
  17
  18 (defvar *current-prefix-arg* nil
  19   "The value of the prefix argument for this editing command.
  20 It may be a number, or the symbol `-' for just a minus sign as arg,
  21 or a list whose car is a number for just one or more C-u's
  22 or nil if no argument has been specified.
  23 This is what `(interactive \"P\")' returns.")
  24
  25 (defvar *command-history* nil
  26   "List of recent commands that read arguments from terminal.
  27 Each command is represented as a form to evaluate.")
  28
  29 (defun call-interactively (function &optional record-flag (keys *this-command-keys*))
  30   "Call FUNCTION, reading args according to its interactive calling specs.
  31 Return the value FUNCTION returns.
  32 The function contains a specification of how to do the argument reading.
  33 In the case of user-defined functions, this is specified by placing a call
  34 to the function `interactive' at the top level of the function body.
  35 See `interactive'.
  36
  37 Optional second arg RECORD-FLAG non-nil
  38 means unconditionally put this command in the command-history.
  39 Otherwise, this is done only if an arg is read using the minibuffer.
  40
  41 Optional third arg KEYS, if given, specifies the sequence of events to
  42 supply, as a vector, if the command inquires which events were used to
  43 invoke it.  If KEYS is omitted or nil, the return value of
  44 `*this-command-keys-vector*' is used."
  45   (setf function (lookup-command function))
  46   (check-type function command)
  47
  48   (let ((args (mapcar (lambda (a)
  49                         (if (listp a)
  50                             (apply (gethash (first a) *command-arg-type-hash*) (cdr a))
  51                             (funcall (gethash a *command-arg-type-hash*))))
  52                       (command-args function))))
  53     ;; XXX: Is this a sick hack?  We need to reset the
  54     ;; prefix-arg at the right time. After the command
  55     ;; is executed we can't because the universal
  56     ;; argument code sets the prefix-arg for the next
  57     ;; command. The Right spot seems to be to reset it
  58     ;; once a command is about to be executed, and
  59     ;; after the prefix arg has been gathered to be
  60     ;; used in the command. Which is right here.
  61     (setf *prefix-arg* nil)
  62     ;; Note that we use the actual function. If the
  63     ;; function is redefined, the command will
  64     ;; continue to be defined and will call the
  65     ;; function declared above, not the redefined one.
  66     (apply (command-fn function) args)))
  67
  68 (defun prefix-numeric-value (prefix)
  69   "Return numeric meaning of raw prefix argument RAW.
  70 A raw prefix argument is what you get from :raw-prefix.
  71 Its numeric meaning is what you would get from :prefix."
  72   ;; TODO
  73   (cond ((null prefix)
  74          1)
  75         ((eq prefix '-)
  76          -1)
  77         ((and (consp prefix)
  78               (integerp (car prefix)))
  79          (car prefix))
  80         ((integerp prefix)
  81          prefix)
  82         (t 1)))