This document contains slides from a lecture on lexical analysis in CSE340 - Principles of Programming Languages. It discusses programming assignment 1, which involves recognizing different lexical elements like integers, identifiers, strings, and keywords. It also shows the process of building a state transition table for a lexer to analyze input and transition between states based on the current character. Homework includes reviewing recursion and solving problem set 1 in preparation for an exam.

1. CSE340 - Principles of
Programming Languages
Lecture 06:
Closing with Lexical Analysis
Javier Gonzalez-Sanchez
javiergs@asu.edu
BYENG M1-38
Office Hours: By appointment

2. Javier Gonzalez-Sanchez | CSE340 | Summer 2015 | 4
Programming Assignment #1
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70%
?
100%

3. Javier Gonzalez-Sanchez | CSE340 | Summer 2015 | 5
Programming Assignment #1
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100%

4. Javier Gonzalez-Sanchez | CSE340 | Summer 2015 | 6
Programming Assignment #1
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70%

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Programming Assignment #1
! Firstname_Lastname_P1.zip
! Compile and Run
! Recognize BINARY
! Recognize DELIMITER and OPERATOR
approx. 20%
! Recognize INTEGER
! Recognize OCTAL
! Recognize HEXADECIMAL
! Recognize IDENTIFIER
approx. 40%
! Recognize STRING
! Recognize CHAR
! Recognize KEYWORD
! Recognize FLOAT
approx. 40%

6. Javier Gonzalez-Sanchez | CSE340 | Summer 2015 | 8
Review | Lexical Analysis
Are the following STRINGS correct or not? Why?
! 000000005
! 000000009
! 000000009.1
! 000000005
! 000000005.1
! 0x0000002
! 0123456789

7. Javier Gonzalez-Sanchez | CSE340 | Summer 2015 | 9
Review | Lexical Analysis
Are the following STRINGS correct or not? Why?
! 1.2e---3++
! $50
! float ________________ = 5;
! double x = 000000.1;
! '''a'
! '''b'
! ''b'

8. Javier Gonzalez-Sanchez | CSE340 | Summer 2015 | 10
Review | Lexical Analysis
Are the following STRINGS correct or not? Why?
! " a"
! "Hello""world"
! abc"Hello"
! ''’
! 'x’
! ’a'
! ’w’
! ""

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State Transition Table
for our Lexer
(step by step)

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BINARY
INTEGER
OCTAL
HEXADECIMAL
IDENTIFIER

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Lexer – Step by Step

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Lexer – Step by Step

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Lexer – Step by Step
1 = INTEGER
2 = INTEGER
3 = IDENTIFIER
5 = OCTAL
7 = INTEGER
8 = IDENTIFIER
9 = BINARY
10 = HEXADECIMAL
columns
[a-z] = [A] B [C-F] [G-W] X [Y-Z]
[a-f] = [A] B [C-F]
0
$
_
[1]
[2-7]
[8-9]
[A]
B
[C-F]
[G-W]
X
[Y-Z]
states

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Lexer – Step by Step
0 $ _ [1] [2-7] [8-9] A B [C-F] [G-W] X [Y-Z] ... Delimiter, operator,
whitespace, quotation
mark
S0! S1$ S3$ S3$ S2$ S2$ S2$ S3$ S3$ S3$ S3$ S3$ S3$ SE! Stop!
S1! S5$ SE! SE! S5$ S5$ SE! SE! S4$ SE! SE! S6$ SE! SE! Stop!
S2! S7$ SE! SE! S7$ S7$ S7$ SE! SE! SE! SE! SE! SE! SE! Stop!
S3! S8$ S8$ S8$ S8$ S8$ S8$ S8$ S8$ S8$ S8$ S8$ S8$ SE! Stop!
S4! S9$ SE! SE! S9$ SE! SE! SE! SE! SE! SE! SE! SE! SE! Stop!
S5! S5$ SE! SE! S5$ S5$ SE! SE! SE! SE! SE! SE! SE! SE! Stop!
S6! S10$ SE! SE! S10$ S10$ S10$ S10$ S10$ S10$ SE! SE! SE! SE! Stop!
S7! S7$ SE! SE! S7$ S7$ S7$ SE! SE! SE! SE! SE! SE! SE! Stop!
S8! S8$ S8$ S8$ S8$ S8$ S8$ S8$ S8$ S8$ S8$ S8$ S8$ SE! Stop!
S9! S9$ SE! SE! S9$ SE! SE! SE! SE! SE! SE! SE! SE! SE! Stop!
S10! S10$ SE! SE! S10$ S10$ S10$ S10$ S10$ S10$ SE! SE! SE! SE! Stop!
SE! SE! SE! SE! SE! SE! SE! SE! SE! SE! SE! SE! SE! SE! Stop!

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Homework
Review Recursion
Solve the Problem Set #1 in preparation for your exam

16. CSE340 - Principles of Programming Languages
Javier Gonzalez-Sanchez
javiergs@asu.edu
Summer 2015
Disclaimer. These slides can only be used as study material for the class CSE340 at ASU. They cannot be distributed or used for another purpose.