Context-free languages

Question 1

What is Backus-Naur form?

Answer 1

A context-free grammar used by developers of programming languages to specify the syntax rules of a language

Question 2

What are production rules?

Answer 2

A range of symbols and expressions combined

Question 3

What are <> used for in BNF?

Answer 3

Denote a non-terminal symbol
A non-terminal symbol appearing on the right side of a production rule means there’ll be another rule after to define the contents of the chevrons

Question 4

What is | | used for in BNF?

Answer 4

Showing terminal symbols, these values cannot be broken down and defined further. They are the building blocks

Question 5

What symbol must be included in BNF statements at some point?

Answer 5

Terminal symbols

Question 6

Can recursion be used in BNF?

Answer 6

Yes

Question 7

What does a parse tree do?

Answer 7

Breaks something down into it’s component parts

Question 8

What are parse trees often used to do?

Answer 8

Check whether a string satisfies a production rule

Question 9

What is the diagrammatic approach to BNF called?

Answer 9

A syntax diagram

Question 10

State the rules of reading a syntax diagram

Answer 10

Read left to right
Follow the arrows
You can’t go back unless a loop arrow is included