X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Ftoplevel.lisp;h=cd9463c4447c7e01a42ebfb3db6890c8cc6ec992;hb=3b7bcf8ff3727a7f68102f7458805d1bebee5e78;hp=a2a141f42f6874ea688e406b8e5b73c88741dea0;hpb=5ec8d0c1c8b7939818b75118b472fac1af554f9a;p=sbcl.git

diff --git a/src/code/toplevel.lisp b/src/code/toplevel.lisp
index a2a141f..cd9463c 100644
--- a/src/code/toplevel.lisp
+++ b/src/code/toplevel.lisp
@@ -459,46 +459,52 @@
   (let ((* nil) (** nil) (*** nil)
 	(- nil)
 	(+ nil) (++ nil) (+++ nil)
-	(/// nil) (// nil) (/ nil)
-	(eof-marker (cons :eof nil)))
+	(/// nil) (// nil) (/ nil))
+    (/show0 "about to set up restarts in TOPLEVEL-REPL")
+    ;; There should only be one TOPLEVEL restart, and it's here, so
+    ;; restarting at TOPLEVEL always bounces you all the way out here.
+    (with-simple-restart (toplevel
+			  "Restart at toplevel READ/EVAL/PRINT loop.")
+      ;; We add a new ABORT restart for every debugger level, so 
+      ;; restarting at ABORT in a nested debugger gets you out to the
+      ;; innermost enclosing debugger, and only when you're in the
+      ;; outermost, unnested debugger level does restarting at ABORT 
+      ;; get you out to here.
+      (with-simple-restart (abort "Reduce debugger level (leaving debugger).")
+	(catch 'toplevel-catcher
+	  (sb!unix:unix-sigsetmask 0)	; FIXME: What is this for?
+	  (repl noprint))))))
+
+(defun repl (noprint)
+  (/show0 "entering REPL")
+  (let ((eof-marker (cons :eof nil)))
     (loop
-      (/show0 "at head of outer LOOP in TOPLEVEL-REPL")
-      ;; There should only be one TOPLEVEL restart, and it's here, so
-      ;; restarting at TOPLEVEL always bounces you all the way out here.
-      (with-simple-restart (toplevel
-			    "Restart at toplevel READ/EVAL/PRINT loop.")
-	;; We add a new ABORT restart for every debugger level, so 
-	;; restarting at ABORT in a nested debugger gets you out to the
-        ;; innermost enclosing debugger, and only when you're in the
-        ;; outermost, unnested debugger level does restarting at ABORT 
-	;; get you out to here.
-        (with-simple-restart (abort
-			      "Reduce debugger level (leaving debugger).")
-	  (catch 'toplevel-catcher
-	    (sb!unix:unix-sigsetmask 0)	; FIXME: What is this for?
-	    (/show0 "about to enter inner LOOP in TOPLEVEL-REPL")
-	    (loop ; FIXME: Do we need this inner LOOP?
-	     ;; FIXME: It seems bad to have GC behavior depend on scrubbing
-	     ;; the control stack before each interactive command. Isn't
-	     ;; there some way we can convince the GC to just ignore
-	     ;; dead areas of the control stack, so that we don't need to
-	     ;; rely on this half-measure?
-	     (scrub-control-stack)
+     ;; FIXME: It seems bad to have GC behavior depend on scrubbing the
+     ;; control stack before each interactive command. Isn't there some
+     ;; way we can convince the GC to just ignore dead areas of the
+     ;; control stack, so that we don't need to rely on this
+     ;; half-measure?
+     (/show0 "at head of LOOP")
+     (scrub-control-stack)
+     (/show0 "back from SCRUB-CONTROL-STACK")
+     (unless noprint
+       (fresh-line)
+       (/show0 "back from FRESH-LINE")
+       (princ (if (functionp *prompt*)
+		  (funcall *prompt*)
+		  *prompt*))
+       (/show0 "back from PRINC")
+       (flush-standard-output-streams)
+       (/show0 "back from FLUSH-STANDARD-OUTPUT-STREAMS"))
+     (let ((form (read *standard-input* nil eof-marker)))
+       (/show0 "back from READ")
+       (if (eq form eof-marker)
+	   (quit)
+	   (let ((results (multiple-value-list (interactive-eval form))))
 	     (unless noprint
-	       (fresh-line)
-	       (princ (if (functionp *prompt*)
-			  (funcall *prompt*)
-			  *prompt*))
-	       (flush-standard-output-streams))
-	     (let ((form (read *standard-input* nil eof-marker)))
-	       (if (eq form eof-marker)
-		   (quit)
-		   (let ((results
-			  (multiple-value-list (interactive-eval form))))
-		     (unless noprint
-		       (dolist (result results)
-			 (fresh-line)
-			 (prin1 result)))))))))))))
+	       (dolist (result results)
+		 (fresh-line)
+		 (prin1 result)))))))))
 
 (defun noprogrammer-debugger-hook-fun (condition old-debugger-hook)
   (declare (ignore old-debugger-hook))
@@ -512,12 +518,14 @@
     (handler-case
 	(progn
 	  (format *error-output*
-		  "~@<unhandled condition (of type ~S): ~2I~_~A~:>~2%"
+		  "~&~@<unhandled condition (of type ~S): ~2I~_~A~:>~2%"
 		  (type-of condition)
 		  condition)
 	  ;; Flush *ERROR-OUTPUT* even before the BACKTRACE, so that
-	  ;; even if we hit an error within BACKTRACE we'll at least
-	  ;; have the CONDITION printed out before we die.
+	  ;; even if we hit an error within BACKTRACE (e.g. a bug in
+	  ;; the debugger's own frame-walking code, or a bug in a user
+	  ;; PRINT-OBJECT method) we'll at least have the CONDITION
+	  ;; printed out before we die.
 	  (finish-output *error-output*)
 	  ;; (Where to truncate the BACKTRACE is of course arbitrary, but
 	  ;; it seems as though we should at least truncate it somewhere.)