Project 8: Translating from POJay to OJay

The goal of this project is for you to devise a way to interpret an a language with polymorphism in a language without it. You will put this into practice by encoding a POJay program into the OJay language. Then, using your OJay to RecJay translator from Project 7 and the RecJay interpreter I provided, you'll have POJay interpreter.

1. Set up

I am giving you an interpreter for RecJay (in Java), you will supply the OJay-to-RecJay translator (in ML) from the previous project, and you will complete a POJay-to-OJay translator (in ML). A script will feed the results of your translator into the RecJay interpreter.

All this is archived in a tar file. Copy the file from the class directory and untar it.

cp /cslab/class/cs365/proj8.tar .
tar xvf proj8.tar

The script file contains the dummy ojay2recjay.sml and pojay2ojay.sml files. Copy your ojay2recjay.sml from last time; I will grade this right away and give you feedback about anything not working. Let me know very soon if you still need a working ojay2recjay, so that this does not impede your progress on the current project.

2. Your task

Your task is to write complete the code in pojay2ojay.sml. This file looks almost exactly like the stub file I gave you last time.

3. Testing your code

There are three driver scripts:

OJay-print will translate from POJay to OJay, feed the result into the OJay-toRecJay translator, and finally print the RecJay translation to the screen, for debugging purposes. Usage:

./OJay-print somefile.pojay

POJay-print will print the OJay translation to the screen, for debugging purposes. Usage:

./POJay-print somefile.pojay

POJay-run will do both translations and execute the final RecJay translation. Usage:

./POJay-run somefile.pojay

4. Turn in

To turn in this project, please copy your ojay2recjay.sml and pojay2ojay.sml to the turn-in directory I will prepare for you:

/cslab/class/cs365/turnin/proj8/xxxxxx

where "xxxxxx" is [andy|david|tyler|yelemis]. I will grade your project by running it against a collection of test files.

NOTE that you are responsible for turning in a working ojay2recjay.sml for this project also.

DUE: Monday Apr 7, 5:00 pm.