The variable
*handle-old-in-package-used-as-make-package*
controls what happens when a CLtL1-style
in-package
form which attempts to create a package is processed. This refers to the specification in Common Lisp the Language, first Edition, which preceded ANSI Common Lisp and specified
in-package
as a function with keyword arguments.
The allowed values are as follows:
Handle according to the value of *handle-old-in-package*.
Signal a warning and create the package.
Signal a continuable error.