STUDY GUIDE
– TEST 2 – CS 424/524: Fall 2014
Material covered: Chapter 4 (Names – applications of the principles ) Chapter 5, 6.1 (Types & Type Systems); parts of Chapter 7 (Semantics), Chapter 9 (Functions), Chapter 15: (Logic Programming and Prolog ).
The structure of the test will be similar to the structure of Test 1: Objective questions, short answer questions, simple programming exercises and other types of problems similar to those found on the homework.
Chapter 4:Names
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Be able to demonstrate understanding of the properties associated with names; for example, problems like those on the last homework assignment.
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Be able to draw a symbol table stack for a certain phase of language translation
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Be able to explain or demonstrate how the symbol table is used during name resolution.
Chapter 5: Types
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Definitions: type, type error, strongly typed, etc. Be able to give an example of a type error.
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Difference between static and dynamic typing
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What are some of the problems associated with number representation in computers?
 What does “overloaded” mean with respect to a function or operator?
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What are the issues connected to mixed type expressions and assignments? (type mismatches, type conversions: implicit (type coercion) or explicit (casts) )
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Enumeration types
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Issues related to pointers and dynamic memory allocation
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Arrays: access functions for one- and two-dimension arrays; row major versus column major storage, dope vectors. Why can’t all array addresses be determined at compile-time? What are the pros and cons of array bounds checking?
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Understand buffer overflow and its relation to arrays.
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Define/identify list, slice, structure, union. Know something about their characteristics.
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Definition of polymorphism. What is parametric polymorphism, as exhibited in generic functions or templates?
Chapter 6: Type Systems
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Why are type rules not included as part of the language’s grammar; how are they represented?
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Know the purpose of the Clite type map
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Review the Clite type rules and be able to give several examples of issues they address; for example: type
Rule 6.6 specifies how the result type of an expression is determined.
Chapter 7: Semantics
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Definition of semantics, why is a well-defined semantic system important?
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Program state; semantics as a description of how instructions modify program state
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Expression semantics – various notations (Polish, Cambridge) and their advantages
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Examples of specific semantic issues o Definition of short-circuit evaluation o Side effects: definition, examples, pros and cons. Also see Side Effect slides in Chapter 9. o Understand the problems related to sub-expression evaluation order o Assignment expression versus assignment statement o Copy versus reference semantics
 “Meaning rules” as a way of describing semantics by showing how a program maps one state to the next
Chapter 9: Functions
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Definitions; “caller” versus “called”, value-returning versus void, aliasing, etc.
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Parameter versus argument,
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Parameter passing mechanisms: by value, by reference, by value-result, by result
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Be able to explain/show the difference between two types of parameter passing (e.g. 9.1, page 241)
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Three types of storage; in particular, purose of the run-time stack
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Definition/purpose of activation records; support for recursive functions; contents
– be sure you understand
 all the information that must be saved, not just the parts we’ve included in our examples.
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Run-time stack, understand, be able to reproduce examples such as those on pages 238 & 239
Chapter 15: Logic Programming
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Be able to informally describe the difference between the imperative and logic(declarative) programming paradigms. Give examples of statements that represent this difference
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What is the difference between propositional logic and predicate logic (predicate calculus); basically, you need to know the difference between a proposition and a predicate

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Definitions: Horn clause, resolution (applied to Horn clauses), instantiation, unification. Understand the concepts so if you read a question that has one of these terms you’ll know what it means.
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Be able to read/interpret simple Prolog rules. Given a database of facts and a rule base (such as the family tree or talks-with example) be able to give a solution to a simple query.
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Be able to write simple rules and queries, similar to those on the programming assignment.
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Given facts and rules, be able to tell what the first response to a given query would be, and if there are other responses. (Knowing what the first response is shows that you understand how resolution and backtracking work..
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Be familiar with basic list notation (square brackets and commas to represent the list, [X|Y] to denote the division of the list into its head and tail, etc.)
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Know the difference between rules that are conjunctions and rules that are disjunctions.
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Know what backtracking is, its purpose, and the way Prolog applies it.
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Understand the use of simple lists in Prolog.