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Common Lisp Extensions

C. Old CL Compatibility

Following is a list of all known incompatibilities between this package and the older Quiroz `cl.el' package.

This package's emulation of multiple return values in functions is incompatible with that of the older package. That package attempted to come as close as possible to true Common Lisp multiple return values; unfortunately, it could not be 100% reliable and so was prone to occasional surprises if used freely. This package uses a simpler method, namely replacing multiple values with lists of values, which is more predictable though more noticeably different from Common Lisp.

The defkeyword form and keywordp function are not implemented in this package.

The member, floor, ceiling, truncate, round, mod, and rem functions are suffixed by `*' in this package to avoid collision with existing functions in Emacs. The older package simply redefined these functions, overwriting the built-in meanings and causing serious portability problems. (Some more recent versions of the Quiroz package changed the names to cl-member, etc.; this package defines the latter names as aliases for member*, etc.)

Certain functions in the old package which were buggy or inconsistent with the Common Lisp standard are incompatible with the conforming versions in this package. For example, eql and member were synonyms for eq and memq in that package, setf failed to preserve correct order of evaluation of its arguments, etc.

Finally, unlike the older package, this package is careful to prefix all of its internal names with cl-. Except for a few functions which are explicitly defined as additional features (such as floatp-safe and letf), this package does not export any non-`cl-' symbols which are not also part of Common Lisp.