INSS 510

MIDTERM 2001 TERM 4

Each problem 4 scores

Your Name:

1. Explain the different aspects of the cost of programming language.

2. What major features would a perfect programming language include, in your opinion?

3. Are there any logic programming languages, other than Prolog?

4. Do you think language design by committee is a good idea? Support your opinion.

5. Using the grammar of Example 3.4 from the textbook , show a parse tree and a leftmost derivation for each of the following statements:

a. A := A * (B + (C * A))

b. B := B + C + A

c. A := A * (B +C)

6. Compute the weakest precondition for each of the following assignment statements and postconditions:

a. a := 2* (b - 1) - 1 ß a > 0 ß

b. b := (c + 10) / 3 ß b > 6 ß

7. Describe the situation when a history-sensitive variable in a subprogram is useful.

8. Why does a decimal value waste memory space?

9. What are the arguments for and against representing Boolean values as single bits memory?

_10. Compare the tombstones and locks-and-keys method of avoiding dangling pointers, from the points of view of safety and implementation cost.