Simple Templates

Simple template systems do direct translation, essentially eliminating the internal "knowledge representation" structures described in the prototypical machine translation scenario.

T.S. to translate simplified (restricted) English commands to DOS.

High level description of the system:
   ACCEPTABLE INPUT ===> DOS EQUIVALENT

Almost considered essential to add this element:
   UNACCEPTABLE INPUT ===> ERROR MESSAGE

And in most cases is would be appropriate to also add this:
   ALMOST ACCEPTABLE INPUT ===> DOS EQUIVALENT (with possibility of backing out)

Initial design of system (as well as a description of any similar translation scheme) is just a table:

INPUT	OUTPUT	ACTION (possible provision)
accptbl cmmd1	DOS equiv1	execute command
accptbl cmmd2	DOS equiv2	execute command
:     :     :
accptbl cmmdm	DOS equivm	execute command
almost accptbl cmmd1	DOS equiv1	execute command
almost accptbl cmmd2	DOS equiv2	execute command
:     :     :
almost accptbl cmmdn	DOS equivn	execute command

Possible additions: warnings for "dangerous" commands

Concrete prototype of above translation table

INPUT                                    OUTPUT
-----------------                        --------------------
What is on disk A?                       DIR A:
What is on drive A?                      DIR A:
What is on the disk in drive A?          DIR A:
What is on disk B?                       DIR B:
What is on drive B?                      DIR B:
What is on the disk in drive B?          DIR B:

First abstraction:

We need to handle arbitrary drive names. Solution: create a "token" (syntactic entity) to represent any letter. We'll use _X. [Note how this is like "token classes" in grammars.]

The table becomes:

INPUT                                    OUTPUT
-----------------                        --------------------
What is on disk _X?                       DIR $(_X):
What is on drive _X?                      DIR $(_X):
What is on the disk in drive _X?          DIR $(_X):