0.8.16.2: TYPE-ERROR for ERROR

[sbcl.git] / doc / manual / debugger.texinfo

diff --git a/doc/manual/debugger.texinfo b/doc/manual/debugger.texinfo
index 493471c..6a9e137 100644 (file)
--- a/doc/manual/debugger.texinfo
+++ b/doc/manual/debugger.texinfo
@@ -1,6 +1,6 @@
-@node  The Debugger
+@node Debugger
 @comment  node-name,  next,  previous,  up
-@chapter The Debugger
+@chapter Debugger
 @cindex Debugger
 
 The SBCL debugger (as the CMUCL debugger it was derived from) has very
@@ -35,6 +35,7 @@ indistinguishable from interpreted code debugging.
 * Exiting Commands::            
 * Information Commands::        
 * Function Tracing::            
+* Single Stepping::             
 @end menu
 
 @node  Starting the Debugger
@@ -789,7 +790,7 @@ form have been added or deleted.)
 If the heuristic doesn't work, the displayed source will be wrong, but will
 probably be near the actual source.  If the ``shape'' of the top-level form in
 the source file is too different from the original form, then an error will be
-signaled.  When the heuristic is used, the the source location commands are
+signaled.  When the heuristic is used, the source location commands are
 noticeably slowed.
 
 Source location printing can also be confused if (after the source was
@@ -829,7 +830,7 @@ some properties of the block start location:
 
 @item The block start location may be the same as the true location.
 
-@item The block start location will never be later in the the
+@item The block start location will never be later in the 
 program's flow of control than the true location.
 
 @item No conditional control structures (such as @code{if},
@@ -900,7 +901,7 @@ Level @code{1} plus all interned local variables, source location
 information, and lifetime information that tells the debugger when
 arguments are available (even when @code{speed} is @code{3} or the
 argument is set).
-
+ 
 @item > 2
 Any level greater than @code{2} gives level @code{2} and in addition
 disables tail-call optimization, so that the backtrace will contain
@@ -918,6 +919,10 @@ If @code{debug} is greater than both @code{speed} and @code{space},
 the command @command{return} can be used to continue execution by
 returning a value from the current stack frame.
 
+If @code{debug} is also at least 2, then  the code is @emph{partially
+steppable}. If @code{debug} is 3, the code is @emph{fully steppable}.
+@xref{Single Stepping}, for details.
+
 @end table
 
 As you can see, if the @code{speed} quality is @code{3}, debugger performance is
@@ -1006,20 +1011,19 @@ Displays all the frames from the current to the bottom.  Only shows
 @var{n} frames if specified.  The printing is controlled by @code{*debug-print-variable-alist*}.
 @end deffn
 
-@comment  FIXME (rudi 2004-03-31): sbcl doesn't support breakpoints
-@comment  and stepping as of version 0.8.9.  The `list-locations'
-@comment  command works, but executing a function leads to an error
-@comment  when a breakpoint is hit.  When stepping works, the
-@comment  commented-out section below should be reinstated and the
-@comment  example output updated to correspont to sbcl's behaviour.
+@deffn {Debugger Command} step
+Selects the @code{continue} restart if one exists and starts single stepping.
+@xref{Single Stepping}.
+@end deffn
+
+@c The new instrumentation based single stepper doesn't support
+@c the following commands, but BREAKPOINT at least should be
+@c resurrectable via (TRACE FOO :BREAK T).
 
-@c @node  Breakpoint Commands, , Information Commands, The Debugger
-@c @comment  node-name,  next,  previous,  up
-@c @section Breakpoint Commands
 @c @cindex Breakpoints
 
 @c SBCL supports setting of breakpoints inside compiled functions and
-@c stepping of compiled code.  Breakpoints can only be set at at known
+@c stepping of compiled code.  Breakpoints can only be set at known
 @c locations (@pxref{Unknown Locations and Interrupts}), so these
 @c commands are largely useless unless the @code{debug} optimize quality
 @c is at least @code{2} (@pxref{Debugger Policy Control}).  These
@@ -1064,12 +1068,6 @@ Displays all the frames from the current to the bottom.  Only shows
 @c is specified, delete all breakpoints.
 @c @end deffn
 
-@c @deffn {Debugger Command} step
-@c Step to the next possible breakpoint location in the current function.
-@c This always steps over function calls, instead of stepping into them.
-@c @end deffn
-
-
 @c @menu
 @c * Breakpoint Example::          
 @c @end menu
@@ -1180,5 +1178,34 @@ function entry or exit.
 @comment 0.8.9) in a state of flux.  When it's sorted out, revive the
 @comment cmucl documentation.
 
+@node Single Stepping
+@comment  node-name,  next,  previous,  up
+@section Single Stepping
+@cindex Stepper
+@cindex Single Stepping
+
+SBCL includes an instrumentation based single-stepper for compiled
+code, that can be invoked via the @code{step} macro, or from within
+the debugger. @xref{Debugger Policy Control}, for details on enabling
+stepping for compiled code.
+
+Compiled code can be unsteppable, partially steppable, or fully steppable.
+
+@table @strong
 
+@item Unsteppable
+Single stepping is not possible.
+
+@item Partially steppable
+Single stepping is possible at sequential function call granularity:
+nested function calls cannot be stepped into, and no intermediate
+values are available.
+
+@item Fully steppable
+Single stepping is possible at individual function call argument
+granularity, nested calls can be stepped into, and intermediate values
+are available.
+
+@end table
 
+@include macro-common-lisp-step.texinfo