William Bert

Emacs 24.3 renamed the Common Lisp emulation package from cl to cl-lib. The release notes say that cl in 24.3 is now “a bunch of aliases that provide the old, non-prefixed names”, but I encountered some problems with certain packages searching for–as best I can determine–function names that at some point changed but were not kept around as aliases. This was particularly problematic when trying to run 24.3 on OS X 10.6.8.

In case anyone else runs into this problem, here’s my solution:

1;; Require Common Lisp. (cl in <=24.2, cl-lib in >=24.3.)
2(if (require 'cl-lib nil t)
3  (progn
4    (defalias 'cl-block-wrapper 'identity)
5    (defalias 'member* 'cl-member)
6    (defalias 'adjoin 'cl-adjoin))
7  ;; Else we're on an older version so require cl.
8  (require 'cl))

We try to require cl-lib, and when that succeeds, define some aliases so that packages don’t complain about missing cl-block-wrapper, member*, and adjoin. If it doesn’t succeed, we’re on an older Emacs, so require the old cl.