I'm following Practical Common Lisp Chapter 3 codes.
I've save the following codes to an external files:
(defvar *db* nil)
(defun make-cd (title artist rating ripped)
(list :title title :artist artist :rating rating :ripped ripped))
(defun add-record (cd) (push cd *db*))
(defun dump-db ()
(dolist (cd *db*)
(format t "\~{\~a:\~10t\~a\~%\~}\~%" cd)))
I keep getting the following error when I tried to compile it inside Emacs:
compilation unit finished ;
Undefined variable: ;
*DB* ;
caught 1 WARNING condition
Could someone explain to me what is wrong with the code?
What is the different between compiling the above code vs running each line under SLIME?
thanks in advance.
the following is what i tried:
If i try compile all the above codes (cursor at very end), i get the undefined variable warning.
if i try and compile
(defvar *db* nil)
then rest of the code, I don't get the undefined variable warning (i tried this just before posting, but i was not getting this result in previous attempt, or maybe i did something extra in those previous attempts...).
i think i understand why I'm not getting an error with the 2nd method because the *db* is in memory already.
See the SLIME manual: Compilation Commands
C-c C-c only compiles individual toplevel forms. See the documentation how to compile a region or file.
As the people commented - that was also my suspicion that you didn't run the compiling command for the entire buffer.
To compile the entire file/buffer, do: C-c C-k.
Or mark all the code you want by
C-S- and for up p, down n, back b, forward f to be run
and then call M-x slime-compile-region.
Related
I have created a small project using Steel Bank Common Lisp and I am using ASDF to compile and load it. The load command is:
(asdf:load-system :<my-system>)
Everything works fine (the program gets compiled and runs fine) but I keep getting output like
; compiling file "[...].lisp" (written 13 APR 2014 06:20:03 PM):
; compiling (DEFPACKAGE :<my-package> ...)
; compiling (DEFUN <my-func-1> ...)
; compiling (DEFUN <my-func-2> ...)
; compiling (DEFUN <my-func-3> ...)
each time the program is recompiled.
I suppose this output comes from asdf because I am invoking the application with
sbcl --noinform --noprint --script runner_sbcl.lisp
where runner_sbcl.lisp loads the actual application via asdf:load-system. So I suppose
this output does not come from sbcl.
Is there any way to disable console output in asdf:load-system? I would like to be only notified about compilation errors / warnings.
I could not find any information in the documentation.
what about
(setf *load-verbose* nil)
(setf *load-print* nil)
(setf *compile-verbose* nil)
(setf *compile-print* nil)
?
Why are they set, anyway?
This is my workaround for a similar issue I had with quicklisp's ql:quickload.
(with-output-to-string (*standard-output*)
;; asdf:load-system or ql:quickload..
(asdf:load-system :<your-system>))
I am trying to get live-coding to work in lisp. i have the file t.cl which contains only this line: (loop(write(- 2 1))). Now, when i run the file in bash with sbcl --load t.cl --eval '(quit)', it runs the line, but when I try to edit the file in another terminal and save it while it runs, nothing changes ..
Why your example fails
When running sbcl --load t.cl --eval '(quit)' in a shell, what this does is spin-up a SBCL Lisp image in a process, compile the file and run it. You then modify the file and save it to your disk. This last action is of no concern to the already running SBCL process, which has already compiled the previous file. SBCL read the file once when you asked it to, once it has the compiled instructions to run, it has no reason to look at the file again unless you explicitly ask it to.
A 'live' example with Emacs+SLIME
In order to perform 'live' changes to your running program, you must interact with the already running Lisp image. This is easily doable with Emacs+Slime. You can, for example, have a loop like so:
(defun foo (x) (+ x 3))
(dotimes (it 20)
(format t "~A~%" (foo it))
(sleep 1))
and then recompile foo during execution within the REPL with a new definition:
(defun foo (x) (+ x 100))
Another thread will be used to recompile the function. The new function will be used for future calls as soon as its compilation is finished.
The output in the REPL will look like:
3
4
5
CL-USER> (defun foo (x) (+ x 100))
WARNING: redefining COMMON-LISP-USER::FOO in DEFUN
FOO
103
104
105
...
This would also work with the new definition of foo being compiled from another file as opposed to being entered directly in the REPL.
Working from the system shell
While you can already use the example above for development purposes, you might want to interact with a running SBCL Lisp image from the shell. I am not aware of how to do that. For your exact example, you want to get SBCL to reload eventual files that you have modified. A brief look at the SBCL manual doesn't seem to provide ways to pipe lisp code to an already running SBCL process.
I'm using HT-SIMPLE-AJAX to provide a simple JSON structure over AJAX. It works beautifully if the function defined by defun-ajaxis compiled after the lisp image and the server is started.
If I load the lisp program (with ccl --load) with the function defined, I get this error:
Error: Unbound variable: *AJAX-PROCESSOR*
While executing: #, in process listener(1).
Type :GO to continue, :POP to abort, :R for a list of available restarts.
If continued: Skip loading "/home/hunchentoot/quicklisp/local-projects/gac-man/run.lisp"
Type :? for other options.
The function is as follows:
(defun-ajax machine-info (serial) (*ajax-processor*)
(let* ((serialn (remove #\" serial)))
(concatenate 'string
"Lots of boring stuff" "here")))
The ajax processor is created in another function, called at the start of the program:
(defun start ()
(setup)
(connect-to-database)
(defvar *web-server* (start (make-instance 'hunchentoot:easy-acceptor :port 8080
:document-root #p"~/www/")))
(defvar *ajax-processor*
(make-instance 'ajax-processor :server-uri "/ajax"))
(print "Starting web server...")
(setf *show-lisp-errors-p* t
*show-lisp-backtraces-p* t)
(define-easy-handler (docroot :uri "/") () (docroot)
....
....
(setq *dispatch-table* (list 'dispatch-easy-handlers
(create-ajax-dispatcher *ajax-processor*)))))
And yet if I start everything and then compile in the function through slime later, it works just fine. Why is this error occurring?
I'm using Clozure Common Lisp on 64-bit Linux.
It seems that your defun-ajax form is loaded before the start function has run. That is not surprising. Usually, all code is loaded, and only then the entry point is called.
You should always be very suspicious of defvar, defun, defparameter etc. forms appearing in a function body. They don't belong there. Put them as toplevel forms, so they are loaded as part of the program. Most of the things defined during the run of the start function shown should really be toplevel forms.
I am following Practical Common Lisp. I have followed the example to the tee. When I compile in Emacs C-c C-c I get the following error with this code.
(defun make-cd (title artist rating ripped)
(list :title title :artist artist :rating rating :ripped ripped))
(defvar *db* nil)
(defun add-record (cd)(push cd db))
WARNING: in ADD-RECORD : DB is neither declared nor bound,
it will be treated as if it were declared SPECIAL.
I can't understand what is going wrong. It cant be the code because I have tried in both clisp and sbcl, both get similar errors. Why is this occurring? Could my set-up be wrong?
You made a copy error from this text:
(defun add-record (cd) (push cd *db*))
where *db* (mind the * signs) refers to the previous
(defvar *db* nil)
I have created a small project using Steel Bank Common Lisp and I am using ASDF to compile and load it. The load command is:
(asdf:load-system :<my-system>)
Everything works fine (the program gets compiled and runs fine) but I keep getting output like
; compiling file "[...].lisp" (written 13 APR 2014 06:20:03 PM):
; compiling (DEFPACKAGE :<my-package> ...)
; compiling (DEFUN <my-func-1> ...)
; compiling (DEFUN <my-func-2> ...)
; compiling (DEFUN <my-func-3> ...)
each time the program is recompiled.
I suppose this output comes from asdf because I am invoking the application with
sbcl --noinform --noprint --script runner_sbcl.lisp
where runner_sbcl.lisp loads the actual application via asdf:load-system. So I suppose
this output does not come from sbcl.
Is there any way to disable console output in asdf:load-system? I would like to be only notified about compilation errors / warnings.
I could not find any information in the documentation.
what about
(setf *load-verbose* nil)
(setf *load-print* nil)
(setf *compile-verbose* nil)
(setf *compile-print* nil)
?
Why are they set, anyway?
This is my workaround for a similar issue I had with quicklisp's ql:quickload.
(with-output-to-string (*standard-output*)
;; asdf:load-system or ql:quickload..
(asdf:load-system :<your-system>))