add debugging stuff

debug.fs

@@ -0,0 +1,23 @@
+\ debug.fs contains functions overwritten from the debug.fs in gforth,
+\ to make debugging floatingpoint stuff easier.
+
+: (_debug) ( body ip -- )
+        0 Nesting !
+        BEGIN   Unnest off
+                cr ." Scanning code..." cr C-Formated on
+                swap scanword dbg-ip !
+                cr ." Nesting debugger ready!" cr
+                BEGIN   .s f.s disp-step D-Key
+                WHILE   C-Stop @ 0=
+                WHILE   0 get-next set-bp
+                        dbg-ip @ jump
+                        [ here DebugLoop ! ]
+                        restore-bp
+                REPEAT
+                Nesting @ 0= IF EXIT THEN
+                -1 Nesting +! r>
+                ELSE
+                get-next >r 1 Nesting +!
+                THEN
+                dup
+        AGAIN ;