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The Representation

In order to implement these transformations we keep both relators in one structure we call a tuple. In this implementation a tuple is representated as a lisp cons cell. The car of the cell is a string representing the first relator. The cdr of the cell is a string representing the second relator.

Each of the twelve transformation functions takes this pair of relators and returns a new pair containing the transformation. This generates a lot of cons cells.

A more efficient, but not yet implemented, implementation will be to destructively modify the tuple and reuse the cons cell. A further optimization is to keep a pool of strings of a given length and reuse the string storage. This is future work.


root 2004-05-05