Preamble to the Gnu Lesser General Public License

Copyright (c) 2016 Franz Inc., 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.
