PL Chapter 03 04

What is the lowest-level syntactic unit of a language, i.e. most basic units that you can see in a source code?

• Sentence

• Language

• Lexeme

• Token

Is a context-free grammar (CFG) a recognizer or a generator?

• Recognizer

• Generator

• Both

• None

If we can generate two different parse trees for the same sentence, it means the language is:

• a context-free language

• in BNF form

• ambiguous

• infinite

In a language when we say x=4.56 x becomes a double automatically. So, the type here is a ... attribute.

• synthesized

• inherited

a = b + 3 {a > 1}

what is the weakest precondition for this statement?

• b>-2

• b>2

• b<-2

• b<2

Which are the most common top-down parsing algorithms?

• Recursive descent

• LR parsers

• LL parsers

• RR parsers

What is this?

• Recursive descent parsing table

• LL parsing table

• LR parsing table

• RR parsing table

LR parsing is a ..... parsing algorithm.

• top-down

• bottom-up

In LR parsing, what do S and R stand for?

• Shift & Right

• Stack & Read

• Stack & Reduce

• Shift & Reduce

• Shift & Read

What is the most common bottom-up parsing approach?

• LL parsers

• LR parsers

• RR parsers

• RL parsers