;>>>>>>>>>>>>>>>>>>>>>>  init.lsp  <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
;
;  This file is read whenever ibuki common lisp starts.  It contains
;  functions that some find indispensible when using Common LISP, such
;  as "xif" which implements a much more readable version of "if".


;------------------------------------------------------------
;  MACRO:    xif then elsif ... else
;
;
;  This macro allows us to write CONDs using a more natural
;  (at least to us old C programmers) notation.  For example:
;
;         (xif (C1)
;             then (F1_1) (F1_2) (F1_3) ...
;          elsif (C2)
;             then (F2_1) (F2_2) (F2_3) ...
;          elsif (C3)
;             then (F3_1) (F3_2) (F3_3) ...
;          ...
;          else
;             (Fn_1) (Fn_2) (Fn_3) ...
;         )
;         
;  turns into this before evaluation:
;         
;         (cond ((C1) (F1_1) (F1_2) (F1_3) ...)
;               ((C2) (F2_1) (F2_2) (F2_3) ...)
;               ((C3) (F3_1) (F3_2) (F3_3) ...)
;               (t    (Fn_1) (Fn_2) (Fn_3) ...)
;         )
;         
;         


(defmacro xif (&rest form)

    (let (wholecond caselimb)

         (setq wholecond '(cond))

         (setq caselimb (list (car form)))   ; initial (C1)

         (cond ((not (equal (cadr form) 'then))
                  (print "missing then keyword")
                  (return-from xif nil)
               )
         )

         (setq form (cddr form))   ;go past "then" keyword

         (dolist (x form)
              (cond ((equal x 'elsif)
                         (setq wholecond (append wholecond
                                          (list caselimb)))
                         (setq caselimb nil)
                    )
                    ((equal x 'then)
                         nil   ; ignore then keywords
                    )
                    ((equal x 'else)
                         (setq wholecond (append wholecond
                                          (list caselimb)))
                         (setq caselimb '(t))
                    )
                    (t
                         (setq caselimb (append caselimb (list x)))
                    )
              )
         )
         (append wholecond (list caselimb))
    )
)


(defun showfunc (xxxname)
      (pprint (symbol-function xxxname))
)

(defmacro append-m (main-form &rest forms)
  (let (formlist)
     (dolist (one-form forms)
         (setq formlist
               (append formlist
                       (list (list 'setq main-form
                                 (list 'append main-form (list 'list one-form))
                       ))
               )
         )
     )
     (append (list 'let 'nil) formlist)
  )
)

(defun notequal (x y)
     (not (equal x y))
)

(defun nthelem (n list)
     (nth (1- n) list)
)

(defun notnull (x)
     x
)

(defun rchar (xxxword index)
    (char xxxword (1- (- (length xxxword) index)))
)

(defun vi (filename)
    (if (not (stringp filename))
        (progn (princ "You MUST give vi a string as the filename!")(terpri))
        (system (concatenate 'string "vi " filename))
    )
)

(defun emacs (filename)
    (if (not (stringp filename))
        (progn (princ "You MUST give a emacs string as the filename!")(terpri))
        (system (concatenate 'string "emacs " filename))
    )
)


(defun emacs-load (filename)
    (if (not (stringp filename))
        (progn (princ "You MUST give a emacs string as the filename!")(terpri))
        (progn
            (system (concatenate 'string "emacs " filename))
            (load filename)
    )   )
)