Lesson 05

Question 1

What is syntax directed translation ?

Answer 1

is done by attaching rules or program fragments to productions in a grammar

Question 2

Attribute ?

Answer 2

any quantity associated with a programming construct

Question 3

translation scheme ?

Answer 3

a notation for attaching program fragments of a grammar

Question 4

program fragments

Answer 4

are executed when the production is used during syntax analysis

Question 5

Examples of attributes are

Answer 5

Data types of expressions , Number of instructions in the generated code,
The location of the first instruction in the generated code

Question 6

when we say an attribute is synthesized ?

Answer 6

if its value at a parse-tree node N is determined from attribute values at the children of N and at N itself.

Question 7

Tree traversals

Answer 7

are used for describing attribute evaluation and for specifying the execution of code fragments in a translation scheme.

Question 8

semantic actions.

Answer 8

Program fragments embedded within production bodies

Question 9

translation scheme implementation must ensure

Answer 9

Semantic actions are performed in the order they would appear during a postorder traversal of a parse tree.

Question 10

preorder traversal action

Answer 10

is done when we first visit a node

Question 11

postorder traversal action

Answer 11

is done just before we leave a node for the last time