This Old Lisp

I (rme) was invited to give a talk at this year’s European Lisp Symposium in Marbella, Spain.  It was a great conference.  I highly recommend that you try to attend next the next one if you possibly can.  It will be in Genoa, Italy.  See

Anyway, I prepared a web site that contains a video of the talk and also a written transcript with slides included in the text in the appropriate places.

The link is

It’s not really very technical in nature (it’s meant to be entertaining and encouraging), but maybe some of you would enjoy it.

Clozure CL 1.11.5 is now available

I’m pleased to announce that version 1.11.5 of Clozure Common Lisp is now available.

This release brings the 1.11 branch up-to-date with current OS releases, and contains numerous bug fixes.

The fasl file version has not changed, so there is no need to recompile all your code.

With this release, CCL no longer relies on the old Subversion repository. Although the old Subversion repository will remain online for the foreseeable future, please be sure to look to GitHub for the most up-to-date versions of CCL. contains the details of how to download a copy.  Alternatively, you may go straight to the GitHub release page for 1.11.5.

Development on Clozure CL has slowed greatly over the past couple of years, but now is the time to revitalize it.  This release is an initial step in that direction.

Please use to report bugs or enhancement requests.

Clozure Associates has long supported the development of CCL.  But CCL is not now, nor has it ever been, Clozure Associates’ proprietary product.  The project welcomes and needs contributions from its users.  Thus, if you’d be interested in helping with CCL, by writing code, documentation, or by any other means, please let me ( know how I can help you do that.

Customizing the listener prompt

Clozure CL’s default prompt is “? “.  You can customize this by setting ccl:*listener-prompt-format* to a format control of your choice.

Note that a format control “string” can be a function.  Here’s an example that makes the prompt contain the current package name.

(defun prompt-formatter (stream break-level)
  (princ (package-name *package*) stream)
  (if (plusp break-level)
    (format stream " ~d > " break-level)
    (write-string "> " stream)))

To start using this, do

(setq ccl:*listener-prompt-format* #'prompt-formatter)

Clozure CL 1.11 pre-release available for testing

A pre-release version of Clozure CL 1.11 is now available for testing.

Please use Subversion to get a copy. For example, to get the 1.11 pre-release for Linux/x86, you would type (where the $ is the shell prompt)

$ svn co

To get a version for a different platform, change the linuxx86 to one of darwinx86, freebsdx86, solarisx86, windows, or linuxarm.

They hardly merit a mention, but draft release notes are available for your perusal.

If you find problems, the best way to report them is to use After you register and sign in, click on “New Ticket” in the top navigator bar. If you don’t want to register, you can send mail to openmcl-devel or to me ( privately.

Thank you for any testing that you are willing to do. After a short period of testing and bug fixing, I will build updated binaries and make the 1.11 release official.