Instructor’s # t r Solutions # t r Manual
to
Concepts of Programming Languages
#tr #tr #tr
Twelfth #trEdition
R.W. #trSebesta
SCHOLARVAULT
,Preface
Changes for the Twelfth Edition
he goals, overall structure, and approach of this twelfth edition of
T Concepts of Programming Languages remain the same as those of the
eleven earlier editions. The principal goals are to introduce the
fundamental constructs of contemporary programming languages and to
provide the reader with the tools necessary for the critical evaluation of
existing and future programming languages. A secondary goal is to prepare the
reader for the study of compiler design, by providing an in-depth discussion of
programming language structures, presenting a formal method of describing
syntax, and introducing approaches to lexical and syntactic analysis.
The twelfth edition evolved from the eleventh through several different kinds
of changes. To maintain the currency of the material, nearly all of the discussion
of some programming languages, specifically Lua and Objective-C, has been
removed. Material on the newer language, Swift, was added to several chapters.
In addition, a new section on optional types was added to Chapter 6. Material
was added to Section 8.3.4 to describe iterators in Python. In numerous places in
the manuscript small changes were made to correct and/or clarify the discussion.
The Vision
This book describes the fundamental concepts of programming languages by
discussing the design issues of the various language constructs, examining the
design choices for these constructs in some of the most common languages, and
critically comparing design alternatives.
Any serious study of programming languages requires an examination of
some related topics, among which are formal methods of describing the syntax
and semantics of programming languages, which are covered in Chapter 3. Also,
implementation techniques for various language constructs must be considered:
Lexical and syntax analysis are discussed in Chapter 4, and implementation of
2
SCHOLARVAULT
, subprogram # tr linkage # tr is #tr covered #tr in # tr Chapter #tr 10.
# tr Implementation # tr of # tr some # tr other #trlanguage #trconstructs #tris #trdiscussed
#tr in #trvarious #trother #trparts #trof #trthe #trbook.
The #trfollowing #trparagraphs #troutline #trthe #trcontents #trof #trthe #trtwelfth #tredition.
Chapter Outlines
#tr
Chapter #tr1 #trbegins #trwith #tra #trrationale #trfor #trstudying #trprogramming #trlanguages.
#tr It #tr then #tr discusses #tr the #tr criteria #tr used #tr for #tr evaluating #tr programming
#tr languages #trand #trlanguage #trconstructs. #trThe #trprimary #trinfluences #tron #trlanguage
#tr design, #tr common #tr design #tr trade- #tr offs, #tr and #tr the #tr basic #tr approaches #tr to
#tr implementation #trare #tralso #trexamined.
Chapter #tr 2 #tr outlines #tr the #tr evolution #tr of #tr the #tr languages #tr that #tr are
#tr discussed #trin #trthis #trbook. #trAlthough #trno #trattempt #tris #trmade #trto #trdescribe #trany
#tr language #trcompletely, #trthe #trorigins, #trpurposes, #trand #trcontributions #trof #treach
#tr are #trdiscussed. #trThis #trhistorical #troverview #tris #trvaluable, #trbecause #trit #trprovides
#tr the #trbackground #trnecessary #trto #trunderstanding #trthe #trpractical #trand #trtheoretical
#tr basis #trfor #trcontemporary #trlanguage #trdesign. #trIt #tralso #trmotivates #trfurther #trstudy
of #trlanguage #trdesign #trand #trevaluation. #trBecause #trnone #trof #trthe #trremainder #trof
#tr
#tr the #tr book #trdepends #tron #trChapter #tr 2, #trit #trcan #trbe #trread #tron #trits #tr own,
#tr independent #trof #trthe #trother #trchapters.
Chapter #tr3 #trdescribes #trthe #trprimary #trformal #trmethod #trfor #trdescribing #trthe
#tr syntax #tr of #tr programming #tr language—BNF. #tr This #tr is #tr followed #tr by #tr a
#tr description #trof #trattribute #trgrammars, #trwhich #trdescribe #trboth #trthe #trsyntax #trand
#tr static #tr semantics #tr of #tr languages. #tr The #tr difficult #tr task #tr of #tr semantic
#tr description #tris #trthen #trexplored, #trincluding #trbrief #trintroductions #trto #trthe #trthree
#tr most #tr common #tr methods: #tr operational, #tr denotational, #tr and #tr axiomatic
#tr semantics.
Chapter #tr4 #trintroduces #trlexical #trand #trsyntax #tranalysis. #trThis #trchapter #tris
#tr targeted #trto #trthose #trComputer #trScience #trdepartments #trthat #trno #trlonger #trrequire
#tr a #trcompiler #trdesign #trcourse #trin #trtheir #trcurricula. #trSimilar #trto #trChapter #tr2, #trthis
#tr chapter #trstands #tralone #trand #trcan #tr be #trstudied #trindependently #trof #trthe #trrest
#tr of #trthe #trbook, #trexcept #trfor #trChapter #tr3, #tron #trwhich #trit #trdepends.
Chapters #tr5 #trthrough #tr14 #trdescribe #trin #trdetail #trthe #trdesign #trissues #trfor #trthe
#tr primary #trconstructs #trof #trprogramming #trlanguages. #trIn #treach #trcase, #trthe #trdesign
#tr choices #trfor #trseveral #trexample #trlanguages #trare #trpresented #trand #trevaluated.
#tr Specifically, #trChapter #tr5 #trcovers # t r the #trmany #trcharacteristics #trof #trvariables,
3
SCHOLARVAULT
, #tr Chapter #tr6 #trcovers #trdata #trtypes, #trand #trChapter #tr7 #trexplains #trexpressions #trand
#tr assignment #tr statements. #tr Chapter #tr 8 #tr describes #tr control #tr statements, #tr and
#tr Chapters #tr 9 #tr and #tr 10 #tr discuss #tr subprograms #tr and #tr their #tr implementation.
#tr Chapter #t r 11 #tr examines #tr data #tr abstraction #tr facilities. #tr Chapter #tr 12
#tr provides # t r an # t r in-depth
4
SCHOLARVAULT
to
Concepts of Programming Languages
#tr #tr #tr
Twelfth #trEdition
R.W. #trSebesta
SCHOLARVAULT
,Preface
Changes for the Twelfth Edition
he goals, overall structure, and approach of this twelfth edition of
T Concepts of Programming Languages remain the same as those of the
eleven earlier editions. The principal goals are to introduce the
fundamental constructs of contemporary programming languages and to
provide the reader with the tools necessary for the critical evaluation of
existing and future programming languages. A secondary goal is to prepare the
reader for the study of compiler design, by providing an in-depth discussion of
programming language structures, presenting a formal method of describing
syntax, and introducing approaches to lexical and syntactic analysis.
The twelfth edition evolved from the eleventh through several different kinds
of changes. To maintain the currency of the material, nearly all of the discussion
of some programming languages, specifically Lua and Objective-C, has been
removed. Material on the newer language, Swift, was added to several chapters.
In addition, a new section on optional types was added to Chapter 6. Material
was added to Section 8.3.4 to describe iterators in Python. In numerous places in
the manuscript small changes were made to correct and/or clarify the discussion.
The Vision
This book describes the fundamental concepts of programming languages by
discussing the design issues of the various language constructs, examining the
design choices for these constructs in some of the most common languages, and
critically comparing design alternatives.
Any serious study of programming languages requires an examination of
some related topics, among which are formal methods of describing the syntax
and semantics of programming languages, which are covered in Chapter 3. Also,
implementation techniques for various language constructs must be considered:
Lexical and syntax analysis are discussed in Chapter 4, and implementation of
2
SCHOLARVAULT
, subprogram # tr linkage # tr is #tr covered #tr in # tr Chapter #tr 10.
# tr Implementation # tr of # tr some # tr other #trlanguage #trconstructs #tris #trdiscussed
#tr in #trvarious #trother #trparts #trof #trthe #trbook.
The #trfollowing #trparagraphs #troutline #trthe #trcontents #trof #trthe #trtwelfth #tredition.
Chapter Outlines
#tr
Chapter #tr1 #trbegins #trwith #tra #trrationale #trfor #trstudying #trprogramming #trlanguages.
#tr It #tr then #tr discusses #tr the #tr criteria #tr used #tr for #tr evaluating #tr programming
#tr languages #trand #trlanguage #trconstructs. #trThe #trprimary #trinfluences #tron #trlanguage
#tr design, #tr common #tr design #tr trade- #tr offs, #tr and #tr the #tr basic #tr approaches #tr to
#tr implementation #trare #tralso #trexamined.
Chapter #tr 2 #tr outlines #tr the #tr evolution #tr of #tr the #tr languages #tr that #tr are
#tr discussed #trin #trthis #trbook. #trAlthough #trno #trattempt #tris #trmade #trto #trdescribe #trany
#tr language #trcompletely, #trthe #trorigins, #trpurposes, #trand #trcontributions #trof #treach
#tr are #trdiscussed. #trThis #trhistorical #troverview #tris #trvaluable, #trbecause #trit #trprovides
#tr the #trbackground #trnecessary #trto #trunderstanding #trthe #trpractical #trand #trtheoretical
#tr basis #trfor #trcontemporary #trlanguage #trdesign. #trIt #tralso #trmotivates #trfurther #trstudy
of #trlanguage #trdesign #trand #trevaluation. #trBecause #trnone #trof #trthe #trremainder #trof
#tr
#tr the #tr book #trdepends #tron #trChapter #tr 2, #trit #trcan #trbe #trread #tron #trits #tr own,
#tr independent #trof #trthe #trother #trchapters.
Chapter #tr3 #trdescribes #trthe #trprimary #trformal #trmethod #trfor #trdescribing #trthe
#tr syntax #tr of #tr programming #tr language—BNF. #tr This #tr is #tr followed #tr by #tr a
#tr description #trof #trattribute #trgrammars, #trwhich #trdescribe #trboth #trthe #trsyntax #trand
#tr static #tr semantics #tr of #tr languages. #tr The #tr difficult #tr task #tr of #tr semantic
#tr description #tris #trthen #trexplored, #trincluding #trbrief #trintroductions #trto #trthe #trthree
#tr most #tr common #tr methods: #tr operational, #tr denotational, #tr and #tr axiomatic
#tr semantics.
Chapter #tr4 #trintroduces #trlexical #trand #trsyntax #tranalysis. #trThis #trchapter #tris
#tr targeted #trto #trthose #trComputer #trScience #trdepartments #trthat #trno #trlonger #trrequire
#tr a #trcompiler #trdesign #trcourse #trin #trtheir #trcurricula. #trSimilar #trto #trChapter #tr2, #trthis
#tr chapter #trstands #tralone #trand #trcan #tr be #trstudied #trindependently #trof #trthe #trrest
#tr of #trthe #trbook, #trexcept #trfor #trChapter #tr3, #tron #trwhich #trit #trdepends.
Chapters #tr5 #trthrough #tr14 #trdescribe #trin #trdetail #trthe #trdesign #trissues #trfor #trthe
#tr primary #trconstructs #trof #trprogramming #trlanguages. #trIn #treach #trcase, #trthe #trdesign
#tr choices #trfor #trseveral #trexample #trlanguages #trare #trpresented #trand #trevaluated.
#tr Specifically, #trChapter #tr5 #trcovers # t r the #trmany #trcharacteristics #trof #trvariables,
3
SCHOLARVAULT
, #tr Chapter #tr6 #trcovers #trdata #trtypes, #trand #trChapter #tr7 #trexplains #trexpressions #trand
#tr assignment #tr statements. #tr Chapter #tr 8 #tr describes #tr control #tr statements, #tr and
#tr Chapters #tr 9 #tr and #tr 10 #tr discuss #tr subprograms #tr and #tr their #tr implementation.
#tr Chapter #t r 11 #tr examines #tr data #tr abstraction #tr facilities. #tr Chapter #tr 12
#tr provides # t r an # t r in-depth
4
SCHOLARVAULT
