diff options
Diffstat (limited to 'emacs/gds-faq.txt')
| -rwxr-xr-x | emacs/gds-faq.txt | 225 |
1 files changed, 0 insertions, 225 deletions
diff --git a/emacs/gds-faq.txt b/emacs/gds-faq.txt deleted file mode 100755 index b60a2c9ae..000000000 --- a/emacs/gds-faq.txt +++ /dev/null @@ -1,225 +0,0 @@ - -* Installation - -** How do I install guile-debugging? - -After unpacking the .tar.gz file, run the usual sequence of commands: - -$ ./configure -$ make -$ sudo make install - -Then you need to make sure that the directory where guile-debugging's -Scheme files were installed is included in your Guile's load path. -(The sequence above will usually install guile-debugging under -/usr/local, and /usr/local is not in Guile's load path by default, -unless Guile itself was installed under /usr/local.) You can discover -your Guile's default load path by typing - -$ guile -q -c '(begin (write %load-path) (newline))' - -There are two ways to add guile-debugging's installation directory to -Guile's load path, if it isn't already there. - -1. Edit or create the `init.scm' file, which Guile reads on startup, - so that it includes a line like this: - - (set! %load-path (cons "/usr/local/share/guile" %load-path)) - - but with "/usr/local" replaced by the prefix that you installed - guile-debugging under, if not /usr/local. - - The init.scm file must be installed (if it does not already exist - there) in one of the directories in Guile's default load-path. - -2. Add this line to your .emacs file: - - (setq gds-scheme-directory "/usr/local/share/guile") - - before the `require' or `load' line that loads GDS, but with - "/usr/local" replaced by the prefix that you installed - guile-debugging under, if not /usr/local. - -Finally, if you want guile-debugging's GDS interface to be loaded -automatically whenever you run Emacs, add this line to your .emacs: - -(require 'gds) - -* Troubleshooting - -** "error in process filter" when starting Emacs (or loading GDS) - -This is caused by an internal error in GDS's Scheme code, for which a -backtrace will have appeared in the gds-debug buffer, so please switch -to the gds-debug buffer and see what it says there. - -The most common cause is a load path problem: Guile cannot find GDS's -Scheme code because it is not in the known load path. In this case -you should see the error message "no code for module" somewhere in the -backtrace. If you see this, please try the remedies described in `How -do I install guile-debugging?' above, then restart Emacs and see if -the problem has been cured. - -If you don't see "no code for module", or if the described remedies -don't fix the problem, please send the contents of the gds-debug -buffer to me at <neil@ossau.uklinux.net>, so I can debug the problem. - -If you don't see a backtrace at all in the gds-debug buffer, try the -next item ... - -** "error in process filter" at some other time - -This is caused by an internal error somewhere in GDS's Emacs Lisp -code. If possible, please - -- switch on the `debug-on-error' option (M-x set-variable RET - debug-on-error RET t RET) - -- do whatever you were doing so that the same error happens again - -- send the Emacs Lisp stack trace which pops up to me at - <neil@ossau.uklinux.net>. - -If that doesn't work, please just mail me with as much detail as -possible of what you were doing when the error occurred. - -* GDS Features - -** How do I inspect variable values? - -Type `e' followed by the name of the variable, then <RET>. This -works whenever GDS is displaying a stack for an error at at a -breakpoint. (You can actually `e' to evaluate any expression in the -local environment of the selected stack frame; inspecting variables is -the special case of this where the expression is only a variable name.) - -If GDS is displaying the associated source code in the window above or -below the stack, you can see the values of any variables in the -highlighted code just by hovering your mouse over them. - -** How do I change a variable's value? - -Type `e' and then `(set! VARNAME NEWVAL)', where VARNAME is the name -of the variable you want to set and NEWVAL is an expression which -Guile can evaluate to get the new value. This works whenever GDS is -displaying a stack for an error at at a breakpoint. The setting will -take effect in the local environment of the selected stack frame. - -** How do I change the expression that Guile is about to evaluate? - -Type `t' followed by the expression that you want Guile to evaluate -instead, then <RET>. - -Then type one of the commands that tells Guile to continue execution. - -(Tweaking expressions, as described here, is only supported by the -latest CVS version of Guile. The GDS stack display tells you when -tweaking is possible by adding "(tweakable)" to the first line of the -stack window.) - -** How do I return a value from the current stack frame different to what the evaluator has calculated? - -You have to be at the normal exit of the relevant frame first, so if -GDS is not already showing you the normally calculated return value, -type `o' to finish the evaluation of the selected frame. - -Then type `t' followed by the value you want to return, and <RET>. -The value that you type can be any expression, but note that it will -not be evaluated before being returned; for example if you type `(+ 2 -3)', the return value will be a three-element list, not 5. - -Finally type one of the commands that tells Guile to continue -execution. - -(Tweaking return values, as described here, is only supported by the -latest CVS version of Guile. The GDS stack display tells you when -tweaking is possible by adding "(tweakable)" to the first line of the -stack window.) - -** How do I step over a line of code? - -Scheme isn't organized by lines, so it doesn't really make sense to -think of stepping over lines. Instead please see the next entry on -stepping over expressions. - -** How do I step over an expression? - -It depends what you mean by "step over". If you mean that you want -Guile to evaluate that expression normally, but then show you its -return value, type `o', which does exactly that. - -If you mean that you want to skip the evaluation of that expression -(for example because it has side effects that you don't want to -happen), use `t' to change the expression to something else which -Guile will evaluate instead. - -There has to be a substitute expression so Guile can calculate a value -to return to the calling frame. If you know at a particular point -that the return value is not important, you can type `t #f <RET>' or -`t 0 <RET>'. - -See `How do I change the expression that Guile is about to evaluate?' -above for more on using `t'. - -** How do I move up and down the call stack? - -Type `u' to move up and `d' to move down. "Up" in GDS means to a more -"inner" frame, and "down" means to a more "outer" frame. - -** How do I run until the next breakpoint? - -Type `g' (for "go"). - -** How do I run until the end of the selected stack frame? - -Type `o'. - -** How do I set a breakpoint? - -First identify the code that you want to set the breakpoint in, and -what kind of breakpoint you want. To set a breakpoint on entry to a -top level procedure, move the cursor to anywhere in the procedure -definition, and make sure that the region/mark is inactive. To set a -breakpoint on a particular expression (or sequence of expressions) set -point and mark so that the region covers the opening parentheses of -all the target expressions. - -Then type ... - - `C-c C-b d' for a `debug' breakpoint, which means that GDS will - display the stack when the breakpoint is hit - - `C-c C-b t' for a `trace' breakpoint, which means that the start and - end of the relevant procedure or expression(s) will be traced to the - *GDS Trace* buffer - - `C-c C-b T' for a `trace-subtree' breakpoint, which means that every - evaluation step involved in the evaluation of the relevant procedure - or expression(s) will be traced to the *GDS Trace* buffer. - -You can also type `C-x <SPC>', which does the same as one of the -above, depending on the value of `gds-default-breakpoint-type'. - -** How do I clear a breakpoint? - -Select a region containing the breakpoints that you want to clear, and -type `C-c C-b <DEL>'. - -** How do I trace calls to a particular procedure or evaluations of a particular expression? - -In GDS this means setting a breakpoint whose type is `trace' or -`trace-subtree'. See `How do I set a breakpoint?' above. - -* Development - -** How can I follow or contribute to guile-debugging's development? - -guile-debugging is hosted at http://gna.org, so please see the project -page there. Feel free to raise bugs, tasks containing patches or -feature requests, and so on. You can also write directly to me by -email: <neil@ossau.uklinux.net>. - - -Local Variables: -mode: outline -End: |