Basics

Question 1

the form of expressions, statements, and program units of a programming language

Answer 1

Syntax

Question 2

the meaning of the expressions, statements, and program units of a programming language

Answer 2

Semantics

Question 3

include the numeric literals, operators, and special words of a programming language

Answer 3

Lexemes

Question 4

a category of the lexemes of a language

Answer 4

Token

Question 5

reads input strings of the language and decides whether the strings belong to the language.

Answer 5

Language recognizer

Question 6

creates sentences of a language

Answer 6

Language generator

Question 7

describes the syntax of programming languages; a collection of rules

Answer 7

Grammar

Question 8

describe four (4) classes of generative devices or grammars that define four (4) classes of language. Two of these grammar classes are regular and context-free grammar

Answer 8

Noam Chomsky

Question 9

describe the forms of the tokens of the programming languages

Answer 9

Regular grammars

Question 10

describe the syntax of whole programming languages

Answer 10

Context-free grammars

Question 11

a natural notation for describing syntax developed by John Backus and Peter Naur in the mid-1950s

Answer 11

Backus-Naur Form (BNF)

Question 12

a language that is used to describe another language

Answer 12

Metalanguage

Question 13

the abstraction being defined; the text on the left-side of the arrow

Answer 13

Left-hand side (LHS)

Question 14

the definition of LHS; the text to the right of the arrow

Answer 14

Right-hand side (RHS)

Question 15

a mixture of tokens, lexemes, and references to other abstractions

Answer 15

Rule (or production)

Question 16

The abstraction in a BNF description, or grammar, are called

Answer 16

nonterminal symbols or nonterminals

Question 17

The lexemes and tokens of the rules are called

Answer 17

terminal symbols or terminals

Question 18

A rule is recursive if

Answer 18

if its LHS appears in its RHS

Question 19

The sentences of the language are generated through a sequence of applications of the rules, beginning with a special nonterminal of the grammar called the …

This sequence of rule applications is called a …

Answer 19

1. start symbol
2. derivation

Question 20

Each of the strings in the derivation is called a …

Answer 20

sentential form

Question 21

In leftmost derivation, the replaced nonterminal is always the leftmost nonterminal in the sentential form

Answer 21

true

Question 22

In rightmost derivation, the replaced nonterminal is always the rightmost nonterminal

Answer 22

true

Question 23

hierarchical syntactic structures of the sentences of the languages

Answer 23

Parse trees

Question 24

A grammar is ambiguous if the grammar generates a sentence with more than one (1) leftmost derivation or rightmost derivation

Answer 24

true

Question 25

When an expression includes two (2) operators that have the same precedence, a semantic rule is required to specify which should have precedence. The rule is named …

Answer 25

Associativity

Question 26

When a grammar rule has its LHS also appearing at the beginning of its RHS, the rule is said to be …

Answer 26

left recursive

Question 27

extended versions of BNF that increase the readability and writability of BNF

Answer 27

Extended BNF (or EBNF)

Question 28

What are the three (3) EBNF extensions?

Answer 28

1. Optional parts of an RHS are placed in brackets.
2. Braces are used to indicate that the enclosed part can be repeated indefinitely or left out altogether.
3. When a single element must be chosen from a group, the options are placed in parentheses