C H A P T E R T W O Syntax

Parse Tree for 352 As an Integer Figure 2.1

A Program Fragment Viewed As a Stream of Tokens Figure 2.2

A Simple Lexical Syntax for a Small Language, Jay Figure 2.3

Major Stages in the Compiling Process Figure 2.4

Skeleton Lexical Analysis Method That Returns Tokens Figure 2.5

Conventions for Writing Regular Expressions Figure 2.6

A Concrete Syntax for Assignments and Expressions Figure 2.7

Parse Tree for the Expression x+2*y Figure 2.8

Sketch of a Parse Tree for a Complete Program Figure 2.9

Two Different Parse Trees for the AmbExp 2 – 3 – 4 Figure 2.10

An Ambiguous If Statement Figure 2.11

The “Dangling Else” Grammatical Ambiguity Figure 2.12

EBNF-Based Parse Tree for the Expression x+2*y Figure 2.13

Syntax Diagram for Expressions with Addition Figure 2.14

Abstract Syntax for Expression, Assignment, and Loop Figure 2.15

(a) Structure of a Binary Node (a) Structure of a Binary Node. (b) Abstract Syntax Tree for the Expression x+2*y Figure 2.16

Partially Completed Recursive Descent Parse for Assignments Figure 2.17

Algorithm for Writing a Recursive Parser from EBNF Figure 2.18

An Example Jay Program to Compute the nth Fibonacci Number Figure 2.19

Sketch of the Abstract Syntax of a Jay WhileStatement Figure 2.20