Preamble to the Gnu Lesser General Public License

Copyright (c) 2000 Franz Incorporated, Berkeley, CA 94704

The concept of the GNU Lesser General Public License version 2.1

("LGPL") has been adopted to govern the use and distribution of

above-mentioned application. However, the LGPL uses terminology that

is more appropriate for a program written in C than one written in

Lisp. Nevertheless, the LGPL can still be applied to a Lisp program if

certain clarifications are made. This document details those

clarifications. Accordingly, the license for the open-source Lisp

applications consists of this document plus the LGPL. Wherever there

is a conflict between this document and the LGPL, this document takes

precedence over the LGPL.

A "Library" in Lisp is a collection of Lisp functions, data and

foreign modules. The form of the Library can be Lisp source code (for

processing by an interpreter) or object code (usually the result of

compilation of source code or built with some other

mechanisms). Foreign modules are object code in a form that can be

linked into a Lisp executable. When we speak of functions we do so in

the most general way to include, in addition, methods and unnamed

functions. Lisp "data" is also a general term that includes the data

structures resulting from defining Lisp classes. A Lisp application

may include the same set of Lisp objects as does a Library, but this

does not mean that the application is necessarily a "work based on the

Library" it contains.

The Library consists of everything in the distribution file set before

any modifications are made to the files. If any of the functions or

classes in the Library are redefined in other files, then those

redefinitions ARE considered a work based on the Library. If

additional methods are added to generic functions in the Library,

those additional methods are NOT considered a work based on the

Library. If Library classes are subclassed, these subclasses are NOT

considered a work based on the Library. If the Library is modified to

explicitly call other functions that are neither part of Lisp itself

nor an available add-on module to Lisp, then the functions called by

the modified Library ARE considered a work based on the Library. The

goal is to ensure that the Library will compile and run without

getting undefined function errors.

It is permitted to add proprietary source code to the Library, but it

must be done in a way such that the Library will still run without

that proprietary code present. Section 5 of the LGPL distinguishes

between the case of a library being dynamically linked at runtime and

one being statically linked at build time. Section 5 of the LGPL

states that the former results in an executable that is a "work that

uses the Library." Section 5 of the LGPL states that the latter

results in one that is a "derivative of the Library", which is

therefore covered by the LGPL. Since Lisp only offers one choice,

which is to link the Library into an executable at build time, we

declare that, for the purpose applying the LGPL to the Library, an

executable that results from linking a "work that uses the Library"

with the Library is considered a "work that uses the Library" and is

therefore NOT covered by the LGPL.

Because of this declaration, section 6 of LGPL is not applicable to

the Library. However, in connection with each distribution of this

executable, you must also deliver, in accordance with the terms and

conditions of the LGPL, the source code of Library (or your derivative

thereof) that is incorporated into this executable.

End of Document