[Emacs-diffs] Changes to emacs/lisp/subr.el

[Richard M . Stallman]

Index: emacs/lisp/subr.el
diff -c emacs/lisp/subr.el:1.429 emacs/lisp/subr.el:1.430
*** emacs/lisp/subr.el:1.429    Mon Dec  6 15:11:51 2004
--- emacs/lisp/subr.el  Mon Dec 13 19:26:42 2004
***************
*** 1862,1867 ****
--- 1862,1880 ----
         ,@body)
       (quit (setq quit-flag t) nil)))
  
+ (defmacro while-no-input (&rest body)
+   "Execute BODY only as long as there's no pending input.
+ If input arrives, that ends the execution of BODY,
+ and `while-no-input' returns nil.  If BODY finishes,
+ `while-no-input' returns whatever value BODY produced."
+   (declare (debug t) (indent 0))
+   (let ((catch-sym (make-symbol "input")))
+     `(with-local-quit
+        (catch ',catch-sym
+        (let ((throw-on-input ',catch-sym))
+          (when (sit-for 0 0 t)
+            ,@body))))))
+ 
  (defmacro combine-after-change-calls (&rest body)
    "Execute BODY, but don't call the after-change functions till the end.
  If BODY makes changes in the buffer, they are recorded