VLS (Vanilla Lisp Shell)


                               *Introduction*

The Vanilla Lisp Shell (VLS) is designed to provide an Emacs interface
to a Lisp process that from the user's perspective works basically the
same way for every flavor of Lisp.  For example `M-RET' evaluates an
expression and `C-c C-b' produces a back-trace regardless of the type of
Lisp.  VLS will work with any Lisp specification such as Common Lisp or
Scheme and any Lisp implementation such as Allegro Common Lisp or CMU
Common Lisp.

This flexibility is achieved by Lisp type specifics files that have a
simple syntax for associating common symbols with specific Lisp command
strings.  Those common symbol values are then used by VLS commands in
forming a dialog with a specific Lisp process.  VLS provides a
comprehensive set of type specifics files based on current Lisp
implementations, but the user can have his own set of type specifics
files and edit them for customized effects.

VLS tries as much as possible to make the VLS commands work exactly the
same way whether in the Lisp shell buffer or in a Lisp source code file
buffer.  This philosophy allows the Lisp shell buffer to work more like
a free form scratch pad rather than a sequential prompt enter paradigm;
althought the user may operate that way also if that is what they are
accustomed to.

VLS tries to be as intelligent as possible.  For example when evaluating
a form in a Common Lisp file VLS will search the source file and
automatically put the Lisp process in the correct package before
evaluating the form.

Along with the expected Lisp shell capabilities VLS also provides
sophisticated Lisp tools.  One such tool is generalized source code
instrumenting.  Conditional breakpoints are just one example of a source
code instrument.  VLS provides a small useful set of instruments and a
facility to make it easy for the user to add custom instruments.



                               *Installation*

To make VLS unpack it in some directory with

     tar -zxvf *tar-file*

where *tar-file* is the VLS tar file with the `tgz' file extension.
This will create a `vls' sub-directory there.  Change to the `vls'
sub-directory and type either

     ./configure

or

     ./configure --prefix=PATH

By default the first will prepare to install VLS under the default
directory `/usr/local'.  The second will prepare to install VLS under a
directory PATH that you provide.

Then type

     make

To install the made VLS system depending on the operating system and
installation PATH you may need to log in as a super user.  Then type

     make install

The key files that get installed are

     PATH/share/emacs/site-lisp/vls.el
     PATH/share/emacs/site-lisp/vls.elc
     PATH/lib/vls/types
     PATH/lib/vls/extra
     PATH/info/vls.info
     PATH/doc/vls/vls.html

where PATH is the installation directory.



                                  *Using*

To get started you should read the VLS user document.  A quick start can
be tried by just reading the Getting Started chapter.  The `vls.html'
file can be read in a web browser.  So for example if the above PATH was
`/usr/local' you can use the URL

     file:/usr/local/doc/vls/vls.html

Or if you want to read the VLS user document in Emacs with the `info'
command, while in Emacs type

     C-u C-h i /usr/local/info/vls

You can also get a PostScript copy of the VLS document by changing to
the directory where you typed `./configure' and then change to the
sub-directory `doc' and type

     make ps

which will create a PostScript version of the VLS user document called

     vls.ps