Chap 1

Lukman Singleton Chap 1

11. What primitive control statement is used to build more complicate control statements in languages that lack them? The selection statement plus GOTO is used to build more complicated control statements such as FOR loop. 12. What construct of a programming language language provides process abstraction? abstraction? Subprograms 13. What does it mean for a program to be reliable? A program is said to be reliable if it performs to its specifications under all conditions. 14. Why is type checking the parameter of a subprogram important? It can lead to lots of hard to debug errors. 15.What is aliasing? 2 or more distinct names that can be used to access the same memory cell. 16. What is exception handling? The ability of a program to intercept run time errors. 17. Why is readability important to writability? If it is hard to read it is hard to write. 18.How is the cost of compilers for a given language related to the design of that language? Many run time checks will prohibit fast code execution. If optimization is used compiling will  be slower but execution will be faster. 19. What has been the strongest influence on programming language design over the past 50 years? The basic architecture of computers(von Neumann). 20. What is the name of the category of programming languages whose structure is dictated by

the von Neumann computer architecture? Imperative languages 21. What two programming language deficiencies were discovered as a result of the research in software development in the 1970s? Incompleteness of type checking and inadequacy of control statements. 22.What are the three fundamental features of an object-oriented programming language? Data abstraction,inheritance and dynamic (run-time) method. 23.What language was the first to support the three fundamental features of object-oriented  programming? Smalltalk  24.What is an example of two language design criteria that are in direct conflict with each other? Reliability and cost of execution 25. What are the three general methods methods of implementing a programming programming language? Compilation,pure interpretation, hybrid implementation systems 26.Which produces faster program execution, a compiler compiler or a pure interpreter? interpreter? Compiler  27. What role does the symbol table play in a compiler? Serves as a database for the compilation process. 28. What does a linker do? It collects system programs and link them to user programs. 29. Why is the von Neumann bottleneck important? It is the primary limiting factor in the speed of von Neumann architecture computers. 30. What are the advantages of o f implementing a language with a pure interpreter? Easy implementation of many source-level debugging operations, b ecause all run time error 

messages can refer to source level units. 1. Why is useful useful for a programmer programmer to have have some backgroun background d in language language design, design, even though though her  or she may never actually design a programming language? Increased capacity to express ideas, appropriate language choice, learn new languages more easily, easily, better understanding of the significance of o f implementation, better use of already known languages, overall advancement of computing. 2. How can knowledge knowledge of programm programming ing language language characteri characteristic stic benefit benefit the the whole computer  computer  community? If those who choose languages were better informed, perhaps better languages would squeeze out poorer ones. 3. What programmi programming ng language language has dominated dominated scienti scientific fic computing computing over over the past past 50 years? years? FORTRAN 4. What programmi programming ng language language has dominated dominated busines businesss applications applications over the past past 50 years? years? COBOL 5. What programmi programming ng language language has dominate dominate artificial artificial intellig intelligence ence over the past past 50 years? years? LISP 6. In what what languag languagee is UNIX UNIX writt written? en? C 7. What is is the disadvant disadvantage age of having having too many featur features es in a language? language? It tends to lead to knowing only a subset. 8. How can user-de user-defined fined operator operator overloading overloading harm harm the readabili readability ty of a program? program? If the operations are used in odd unintuitive ways. 9. What is is one example example of a lack lack of orthogon orthogonality ality in the design design of C? C has 2 structured data types types (arrays and structs) structs) arrays can be returned returned from functions but structs can't.

10. What language used orthogonality as a primary primary design design choice? Algol 68