+ It is implemented as a "tree" of scheme expressions, as in
+
+ Expr = combine Expr Expr
+ | translate Offset Expr
+ | SCHEME
+ ;
+
+ SCHEME is a Scheme expression that --when eval'd-- produces the
+ desired output.
+
+
+ Because of the way that Molecule is implemented, it is the most
+ efficient to add "fresh" molecules to what you're going to build.
+