| (a) |
Explain what is meant by software design .
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[2] |
| (b) |
The concept of modularity is often discussed in relation to software design.Consider the following two statements: (i)As modularity increases,interface costs increase exponentially. (ii)Modularity allows for more structured,and ultimately more complete,testing to be done. Based on your understanding of software design,discuss in some detail each of the two statements.Explain the extent to which you agree with them,or not.You may use diagrams to illustrate your answers.
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[4] |
| (c) |
Type checking is concerned with the manner in which different data types can appear in the same statement.Consider the following,simplified scenario,involving three new programming languages: •PL/U :a programming language without type-checking •PL/M :a programming language in which different but compatible data types can be mixed;operands are converted into matching types if possible •PL/S :a programming language with strong type-checking:operands must be of exactly the expected type and a collection of four variables: •integers a and b •floating point number c •character d Copy the following table into your answer script.For each of the following arithmetic operations,indicate or state whether the operation will be allowed in each of the languages.Mention any conversions that will occur.
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[9] |
