Compilers

Lexical Analyser

Question 1
Marks : +2 | -2
Pass Ratio : 100%
Which one is a lexer Generator?
ANTLR
DRASTAR
FLEX
All of the mentioned
Explanation:
ANTLR – Can generate lexical analyzers and parsers.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
What goes over the characters of the lexeme to produce value?
Scanner
Parser
Evaluator
Lexical generator
Explanation:
In order to construct a token, the lexical analyzer needs a second stage, the evaluator, which goes over the characters of the lexeme to produce a value.
Question 3
Marks : +2 | -2
Pass Ratio : 100%
The process of forming tokens from an input stream of characters is called __________
Liberalisation
Characterisation
Tokenization
None of the mentioned
Explanation:
The process of forming tokens from an input stream of characters is called tokenization.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
Which grammar defines Lexical Syntax?
Regular Grammar
Syntactic Grammar
Context free Grammar
Lexical Grammar
Explanation:
The specification of a programming language often includes a set of rules, the lexical grammar, which defines the lexical syntax.
Question 5
Marks : +2 | -2
Pass Ratio : 100%
In a compiler the module that checks every character of the source text is called __________
The code generator
The code optimizer
The lexical analyzer
The syntax analyzer
Explanation:
Lexical analysis is the process of converting a sequence of characters into a sequence of tokens.
Question 6
Marks : +2 | -2
Pass Ratio : 100%
Which one is a type of Lexeme?
Identifiers
Constants
Keywords
All of the mentioned
Explanation:
All of them along with Operators are different types of lexemes.
Question 7
Marks : +2 | -2
Pass Ratio : 100%
Which phase of the compiler is Lexical Analyser?
First
Second
Third
None of the mentioned
Explanation:
Lexical Analyzer is First Phase of Compiler.
Question 8
Marks : +2 | -2
Pass Ratio : 100%
Lexers are often generated by a lexer generator, same as parser generators.
True
False
Explanation:
Lexers are often generated by a lexer generator same as parser.
Question 9
Marks : +2 | -2
Pass Ratio : 100%
Which of the lexical analyser can handle Unicode?
Java CC
JFLex
Quex
All of the mentioned
Explanation:
JavaCC – JavaCC generates lexical analyzers written in Java.
Question 10
Marks : +2 | -2
Pass Ratio : 100%
The context free grammar is ambiguous if ______________
The grammar contains non-terminals
Produces more than one parse tree
Production has two non-terminals side by side
None of the mentioned
Explanation:
Since more than one parse tree is generated hence one than option is available .Therefore it’s ambiguous.