Quiz2

Quiz! • Books and papers put away • Hats off or brims turned backwards • Piece of paper out - Name and Student ID on it

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• You have 10 minutes • Turn in papers on first pass by your aisle

Quiz 2 – Type Checking Suppose Oberon had an Enumerated Set type that can be a set of any finite atomic type (BOOLEANS and ranges of INTEGER): VAR smallIntSet: SET OF 1..10; VAR boolSet1, boolSet2: SET OF BOOLEAN; BEGIN smallIntSet := smallIntSet ++ 5;(* insert 5 into set *) boolSet1 := boolSet1 ++ boolSet2; (* union two sets *) END Based on the the Expression Compatibility table for the SET type, below, write a “complete” Oberon type checking testcase for the SET type. Operator | first operand second operand result type -----------------------------------------------------------------------------------++ -- ** | SET OF T T SET OF T | T SET OF T SET OF T | SET OF T SET OF T SET OF T Hint: Expanding this table to include erroneous types (the illegal cases) will help you derive a complete testcase. Hint: You may use symmetries (e.g., commutativity) to reduce the number of cases you write down, but you must note the symmetries in your answer.