90-754 Homework #7: Criteria and Comments
14 April 1999 
A sample solution to is providedhere.  Do not fail to look at the sample!  I feel that few of you really demonstrated significant grasp of this material, and so you will all benefit from a careful examination of my solution to this problem.

Overall criteria for the individual assignment:
Score Description
check Attempted; no actual performance-based grade was given for this assignment
0 No attempt made

Parts a-d
Parts e-i

Parts a-d: Selecting file organization and semantics

Number Description
1.1 Try to think about the justification for your choice based on the likely access patterns of the persistent data in this system.
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Parts e-i: Devising production rules and constructing a sample file

Number Description
5.1 Coordinates will probably need to be two integers, not one.  (You could use one integer if you somehow packed the two numbers into a single-integer representation, but you should have explained that you intended to do this.
5.2 You seem to be assuming the existance of very bizarre and complex parser primitives such as COORDINATE or COLOR.  In real life, these are unlikely to be parser primitives, so you'll have to define the representations for them yourself.
5.3 You need to show explicitly how these forms that you are defining will be represented.
5.4 You have defined a symbol more than once; that is, it appears on the left hand side of the production-definition table more than once.  Yacc will not be able to figure out which of these things you intend to use.
5.5 Your answer does not actually illustrate how these objects will be linked in persistent storage.
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