(matching (otherwise ...)) expands into (cond (otherwise ...)), which
generates an unbound-variable error when executed, because COND does
not special-case OTHERWISE as CASE does.

In some cases, this patch swaps the order of execution of
%TEMPLATE-FOR-MATCH and COLLECT-TEMPLATE-VARS. I'm pretty sure this
doesn't have any noticable effect, but thorough testing is probably
wise.

Same thing, so might as well use the convenience function.

Fixed a couple of problems with some accessors in the NUMBER,
STRUCTURE-OBJECT and STANDARD-OBJECT templates.

System definitions files (.asd and .system) modified in order to make
dependency form CL-PPCRE optional.

Added a few exports and changed the actual package name (i.e., I put
my money where my mouth is; the "published" package name is now a
nickname).

Fixed a couple of snags. APPLY-SUBSTITUTION was not applied
recursively and it was barfing on numbers.
Current version is still incomplete, but it serves as a template for
further development.

Modified Files:
test/unification-tests.lisp
Added Files:
lib-dependent/cl-ppcre-template.lisp

The cl-ppcre-template reuses E. Weitz's wonderful CL-PPCRE library
to provide a seamless (YMMV) reuse of regular expressions within
CL-UNIFICATION.

Added some functionality to extract all variables and/or all values
from an environment or a frame.

Added MATCHF (whose name may change) to simplify the
'destructuring-bind'-like syntax and behavior of the matching
facilities.

Major API change to 'unify'. It now accepts keywords. Old code
shouls not be affected, but new code is now more flexible. Look the
the STRING and (new) CHARACTER methods to see how this change is
affecting the code.

Cleaning up.
Committing in .

Removed Files:
unification.asd unification.system

Clenaing up.
Committing in .

Removed Files:
templates-hierarchy-saved.lisp

Some modification added. Exported symbols and reverted
reader macro #T to construct template instances at read time.
Added MAKE-LOAD-FORM method for templates which should fix problem with
SBCL.

Committing in .

Modified Files:
substitutions.lisp templates-hierarchy.lisp
unification-package.lisp variables.lisp

Made several changes to improve MATCH-CASE (following a note from Ivan
Boldyrev from a long time ago), MATCHING and MATCH.

Else-clauses are now handled correctly (AFAICT).

Single variable templates in MATCH, MATCH-CASE and MATCHING clauses do
not need to be quoted.

MATCHING was generating one gensym'ed variable per clause without
creating an appropriate enclosing LET. This is now fixed.

Changed the top comment and added a (:copier nil) option to the
ENVIRONMENT defstruct, as COPY-ENVIRONMENT is defined later in the
file.

Added the new system building files with more meaningful names
w.r.t. the name of the library.

Marked the two system building files as 'obsolete', before removing
them from the repository. The new files are prefixed by 'cl-'.

Updated copyrights dates and changed a few instructions in the
INSTALLATION file.