Thinking in C++ 2nd ed Volume 1 Revision 6

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TICA4, July 22, 1998: More changes and additions to the “CGI Programming” section at the end of Chapter 23. I think that section is finished now, with the exception of corrections. TICA3, July 14, 1998: First revision with content editing (instead of just being a posting to test the formatting and code extraction process). Changes in the end of Chapter 23 on the “CGI Programming” section. Minor tweaks elsewhere. RTF format should be fixed now. TICA2, July 9, 1998: Changed all fonts to Times and Courier (which are universal); changed distribution format to RTF (readable by most PC and Mac Word Processors, and by at least one on Linux: StarOffice from www.caldera.com. Please let me know if you know about other RTF word processors under Linux). ToDo: Check code listing line widths. Try to add more meaningful names for ‘X’ classes. Put in ad pages. Check separation into header files vs. Implementation files. Differentiate copy-assignment operator= from other forms of operator=. HorseRace game as example of random number generator in early chapter ______________________________________________ The contents of the book, including the contents of the source-code files generated during automatic code extraction, are not intended to indicate any accurate or finished form of the book or source code. Please only add comments/corrections using the form found on http://www.BruceEckel.com/ThinkingInCPP2e.html Please note that the book files are only available in Rich Text Format (RTF) or plain ASCII text without line breaks (that is, each paragraph is on a single line, so if you bring it into a typical text editor that does line wrapping, it will read decently). Please see the Web page for information about word processors that support RTF. The fonts used are Georgia and Verdana, which are available for free download at: http://www.microsoft.com/typography/downloads/georgi32.exe (Georgia for Win95) http://www.microsoft.com/typography/downloads/georgia.exe (Georgia win 3.1)
http://www.microsoft.com/typography/downloads/Georgia.sit.hqx (Georgia Mac) http://www.microsoft.com/typography/downloads/verdan32.exe (verdana 95) http://www.microsoft.com/typography/downloads/verdana.exe (verdana 3.1) http://www.microsoft.com/typography/downloads/Verdana.sit.hqx (verdana mac) If you find any other fonts please report the location. Thanks for your participation in this project. Bruce Eckel
Page 1 and 2: Thinking in C++ 2 nd edition Volume
Page 3 and 4: TICA18: July 29, 1999. Rewrote Chap
Page 5: TICA7, August 14, 1998. Strings cha
Page 9 and 10: In Bruce Eckel President, MindView
Page 11 and 12: MindView Ad Space
Page 13 and 14: Dedication To the scholar, the heal
Page 15 and 16: 2: Making & Using Objects 87 The pr
Page 17 and 18: Type-safe linkage............. 323
Page 19 and 20: protected ............. 618 protect
Page 21 and 22: Preface Like any human language, C+
Page 23 and 24: So the short answer is: what isn’
Page 25 and 26: end up losing some portion of the a
Page 27 and 28: Chapters C++ is a language in which
Page 29 and 30: Chapter 5: Hiding the Implementatio
Page 31 and 32: existing type. In this chapter you
Page 33 and 34: (and official mirror sites) where i
Page 35 and 36: note that the CD ROM is browser-bas
Page 37: Constantine, Lucy Lockwood, Tom Kef
Page 40 and 41: But computers are not so much machi
Page 42 and 43: the solution will run. There’s st
Page 44 and 45: So, although what we really do in o
Page 46 and 47: middle portion is not shown. If you
Page 48 and 49: necessary to achieve the functional
Page 50 and 51: more specific types of trash are de
Page 52 and 53: Shape +draw() +erase() +move() +get
Page 54 and 55: Thermostat Controls Cooling System
Page 56 and 57:
BirdController What happens when fl
Page 58 and 59:
doStuff(c); What’s happening here
Page 60 and 61:
The second approach is to create ob
Page 62 and 63:
Analysis and design The object-orie
Page 64 and 65:
It’s often proposed that you “b
Page 66 and 67:
Phase 1: What are we making In the
Page 68 and 69:
eveal itself in the fullness of tim
Page 70 and 71:
getting into too much detail too ea
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2. Object assembly. As you’re bui
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Phase 4: Iteration This is the poin
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will still function. You need not f
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You’re already on the learning cu
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large, complex program, there’s n
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first time, so it should not be mis
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Performance issues A common questio
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alternatives. Even if you eventuall
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By reading this chapter first, you
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takes several steps. The transition
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variable in another object module,
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point of definition the compiler al
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In a function declaration, you give
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cause the preprocessor to search fo
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until link time, one possibility is
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This book will use Standard C++ (an
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included the header file but all th
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"Hello, world!" And now, finally, t
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int main() { // Specifying formats
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Simple file manipulation Standard I
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This upward compatibility from C to
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iostream object. It’s that simple
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it’s much easier if you have each
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so if you have an array a and you w
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while(in >> word) is what gets the
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Exercises Solutions to selected exe
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If you’ve never seen C before, th
Page 126 and 127:
} x = y = z; // ... It turns out th
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In cfunc( ), the first if that eval
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to a nonzero value). Other conditio
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while(guess != secret) { // Compoun
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curly brace ‘{’. This is in con
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switch(selector) { case integral-va
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using namespace std; void removeHat
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: C03:AutoIncrement.cpp // Shows us
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The first part of the program defin
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: C03:Specify.cpp // Demonstrates t
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All the variables, and even the fun
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from dog, bird is four bytes away f
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: C03:PassByValue.cpp #include usi
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pointers later, but this is arguabl
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All possible combinations of basic
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variable was defined. That is, a sc
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int main() { //.. { // Begin a new
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using namespace std; int globe; voi
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want a value to be extant throughou
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} int i; // The data definition voi
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The const was taken from C++ and in
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Operators and their use This sectio
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Introduction to preprocessor macros
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Bitwise not produces the opposite o
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An interesting bit pattern: unsigne
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x = a * -b; but the reader might ge
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Common pitfalls when using operator
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checking to catch errors. Once you
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(4) Implicit type conversions, norm
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Can't use xp as an X* at this point
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Keyword Meaning xor_eq ^= (bitwise
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The struct declaration must end wit
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int main() { Structure3 s1, s2; Str
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You can see how much more readable
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Once you perform an assignment, the
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for(int i = 0; i < 10; i++) cout
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Even though func1( ) and func2( ) d
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#include using namespace std; int
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++, which “adds one to the pointe
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int* ip = a; P(*ip); P(*++ip); P(*(
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in all upper case. A common flag na
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punctuation are concatenated into a
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Defining a function pointer To defi
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Using a function pointer Once you d
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Make: an essential tool for separat
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multiple rules. Many make programs
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target1.exe: target2.exe: If you ju
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Declare: Declare.o $(CPP) $(OFLAG)D
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lectures, exercises, and guided sol
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values in your instance and print t
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flag. You will need to consult your
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to switch from some language that y
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:~ A tag name like CStashTag is gen
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delete []s->storage; } } ///:~ init
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new unsigned char[newBytes]; The ge
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: C04:CLibTest.cpp //{L} CLib // Te
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Each separate C file is a translati
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of all their function names. So ini
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C library converted to C++ // Decla
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You can see that all the member fun
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: C04:CppLibTest.cpp //{L} CppLib /
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What's an object Now that you’ve
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Object details A question that come
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most of the time, except when struc
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included throughout the system, the
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This will yield a true result, and
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end up “turning off” namespaces
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} void Stack::initialize() { head =
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Read file and store lines in the St
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etween what the user of the structu
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16. Modify Stash to use a vector as
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5: Hiding the Implementation A typi
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The second reason for access contro
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Although func( ) can access any mem
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void Z::initialize() { j = 99; } vo
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private: Holder* h; int* p; public:
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second argument) for n bytes past t
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Any object belonging to this class
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The examples in this book, however,
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void initialize(); void push(void*
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Here’s a simple example demonstra
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u.cleanup(); } ///:~ The only thing
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9. Copy the implementation and test
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This not only provides a single uni
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Now, when an object is defined, voi
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The destructor is called automatica
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eginning of a scope. If a construct
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However, some confusion may result
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pointer “down” (a relative term
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} storage = b; // Point to new memo
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Stack with constructors & destructo
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ut is not responsible for cleaning
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Now if you decide to add another el
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zz[i].print(); } ///:~ Notice that
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Safety during coding is a big issue
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7: Function Overloading & Default A
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Although function overloading is a
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int f(); This works fine when the c
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~Stash(); int add(void* element); v
Page 327 and 328:
Both constructors are exercised in
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Although the member functions civil
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(outside all functions and classes)
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Placeholder arguments Arguments in
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Mem::Mem(int sz) { mem = 0; size =
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int main() { MyString s("My test st
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Notice that a call to ensureMinSize
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7. Create a new version of the Stac
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This provides safety and control in
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const). Storage must be allocated b
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situations, const means “a piece
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has the option of doing constant fo
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const int* const x = &d; // (1) int
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Function arguments & return values
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Returning by value as a const becom
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temporary X. However, f7( ) takes i
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that attempting to modify the desti
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Error: const temporary created by f
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void print(); }; Fred::Fred(int sz)
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until Chapter 10: static. The stati
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The “enum hack” in old code In
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non-const member function. Thus, an
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cq.lastQuote(); // OK //! cq.quote(
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} int main() { const Z zz; zz.f();
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char Comm::read(int index) const {
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9. Write a const pointer to a doubl
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assign via a void* (without a cast)
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In C, one of the ways to preserve e
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granted. In the un-parenthesized ve
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mixed together, so a problem like t
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space than the code generated to do
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Here, the class user never has dire
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void setWidth(int w) { width = w; }
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updateLocal(); return local.tm_sec;
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if(storage != 0) delete []storage;
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The Stack class makes even better u
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Inlines & the compiler To understan
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class Forward { int i; public: Forw
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interface and thereby making the cl
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Because there are actually two stat
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} } exit(1); inline void assure(std
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C++ is complicated enough without a
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second function, without the need f
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10: Name Control Creating names is
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function. C and C++ allow you to cr
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int i; public: X(int ii = 0) : i(ii
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static Obj b inside f( ) and the st
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all you’ve done is change the vis
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Creating a namespace The creation o
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names in an unnamed namespace, you
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Integer a, b, c; Integer divide(Int
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} #endif // USINGDECLARATION_H ///:
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is not very safe. Global data can b
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ws.print(); } ///:~ Here, the quali
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static const X x3; static const X x
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A static member function cannot acc
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int main() { //! Egg x(1); // Error
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zeroing of the storage occupied by
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definition for the Initializer init
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constructor, so you can tell if the
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} static Dependency1 dep1; return d
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across the various translation unit
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that when you give the argument wit
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your namespace into that function s
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a Mirror object, which it assigns t
Page 460 and 461:
Although references also exist in P
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2. Once a reference is initialized
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} ///:~ The call to f(1) produces a
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how does the compiler know how to p
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farther to provide storage for the
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output for bigfun( ), you can see i
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When the local object goes out of s
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} }; int HowMany2::objectCount = 0;
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cout.width(width); cout
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Temporary objects Line 15 begins th
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cout
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Here’s an example: //: C11:NoCopy
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combined with the object dereferenc
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fp = &Simple2::f; } ///:~ In the de
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underlying implementation without a
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the member functions const and prov
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21. Create a simple class without a
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The difference is that the argument
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} }; i += rv.i; return *this; int m
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operator++(Integer& a); // Postfix:
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} Byte operator!() const { cout
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an example of all the operators you
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friend int operator=(const Integer&
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if(&left == &right) {/* self-assign
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} #define TRYC(OP) \ out
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%= right.b; return *this; } Byte& o
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} Byte b3 = 92; b1 = b2 = b3; int m
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ack the object that was changed. Th
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left-hand side of an equal sign. Th
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class ObjContainer { vector a; publ
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#include #include "../require.h" u
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pointer,” although the example sh
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around and calls operator( ) for th
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eturn i[x]; } friend ostream& opera
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Operator &= |= %= >>=
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When you create an operator=, you m
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} ~Dog() { cout
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it. However, if your object require
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: p(dog), houseName(house) { cout
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Before you make any modifications (
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Automatic operator= creation Becaus
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In this case, automatic type conver
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Reflexivity One of the most conveni
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using namespace std; class Stringc
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: C12:TypeConversionFanout.cpp clas
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(the creator of the class) or the u
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16. Add an int data member to both
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13: Dynamic Object Creation Sometim
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Object creation When a C++ object i
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... sometime later: obj->destroy();
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with a call to free( )). Just as a
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Before a pointer to that block is r
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If you have a memory leak in your p
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The other change is the replacement
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can prevent a memory leak (more ele
Page 571 and 572:
However, for the string pointers, i
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Now the array elements in q can be
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Another issue is heap fragmentation
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} free(m); class S { int i[100]; pu
Page 579 and 580:
} for(int i = 0; i < psize; i++) if
Page 581 and 582:
empty bracket syntax to indicate ar
Page 583 and 584:
In both cases you’re handed the s
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When the program runs, it does not
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Notice that operator new only retur
Page 589 and 590:
5. Repeat the above exercise, but a
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14: Inheritance & Composition One o
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int i; public: X() { i = 0; } void
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public: Y() { i = 0; } int change()
Page 597 and 598:
The solution is simple: Call the co
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This makes built-in types act a lit
Page 601 and 602:
#define CLASS(ID) class ID { \ publ
Page 603 and 604:
properly reverse the order of the c
Page 605 and 606:
in the new class. In the next chapt
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Name hiding comes into play here be
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~GameBoard() { cout
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ecause that function was not explic
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implementation hiding themselves, s
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} operator ifstream&() { return fil
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inherit privately, you’re “impl
Page 619 and 620:
int read() const { return i; } void
Page 621 and 622:
organic, evolutionary creature, rat
Page 623 and 624:
your diagrams any way you find help
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Child object to a Parent& (if you c
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#include #include using namespace
Page 629 and 630:
types inside the new type. Typicall
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class BusinessTraveler from Travele
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15: Polymorphism & Virtual Function
Page 635 and 636:
quickly see the usefulness of this
Page 637 and 638:
“narrow” that interface, but ne
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virtual void play(note) const { cou
Page 641 and 642:
class Brass : public Wind { public:
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The keyword virtual tells the compi
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pointer (the VPTR) into the structu
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instrument pointer brass object VPT
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call word ptr [bx+4] Finally, the s
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from the previous assembly-language
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instrument virtual void play() virt
Page 655 and 656:
cout
Page 657 and 658:
may be a common piece of code that
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virtual string sit() const { return
Page 661 and 662:
the examples you’ve seen here, an
Page 663 and 664:
exists) and Dog, which no longer ex
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x = d2.f(); //! d2.f(s); // string
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int main() { Bird b; Cat c; Pet* p[
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Order of constructor calls The seco
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that is called last. This is anothe
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int main() { Base1* bp = new Derive
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The only distinction occurs when yo
Page 677 and 678:
ely on portions of an object that h
Page 679 and 680:
} Object* peek() const { return hea
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Creating containers that hold Objec
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using namespace std; class Shape {
Page 685 and 686:
picture” of class relationships.
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12. Create a model of a greenhouse
Page 689 and 690:
has no default constructor, so why
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16: Introduction to Templates Inher
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} int pop() { return stack[top > 0
Page 695 and 696:
need an object, create it with new,
Page 697 and 698:
object-based hierarchy with its con
Page 699 and 700:
code. The container no longer holds
Page 701 and 702:
In main( ), you can see how easy it
Page 703 and 704:
people see software as a service, a
Page 705 and 706:
} }; class Number { float f; public
Page 707 and 708:
}* head; public: Stack() : head(0)
Page 709 and 710:
changeable throughout the lifetime
Page 711 and 712:
#ifndef AUTOCOUNTER_H #define AUTOC
Page 713 and 714:
The destructor for CleanupCheck doe
Page 715 and 716:
in the program, and you don’t nec
Page 717 and 718:
int main() { Stack ac; // Ownership
Page 720 and 721:
array, copying the old array to the
Page 722 and 723:
of the underlying container) for an
Page 724 and 725:
} friend ostream& operator
Page 726 and 727:
} // Jump an iterator forward itera
Page 728 and 729:
void push(T* dat) { head = new Link
Page 730 and 731:
dereference operator performs the e
Page 732 and 733:
To create the end sentinel: iterato
Page 734 and 735:
} inflate(); storage[next++] = elem
Page 736 and 737:
int main() { { // To force destruct
Page 738 and 739:
class Square : public Shape { publi
Page 740 and 741:
drawAll(p); cout
Page 742 and 743:
that, to acquire a library from a t
Page 744 and 745:
16. (Advanced) Modify PointerToMemb
Page 746 and 747:
Although many of these issues have
Page 748 and 749:
Begin and end comment tags A very i
Page 750 and 751:
void func(int a) { you immediately
Page 752 and 753:
The issue of where to put the openi
Page 754 and 755:
Use of require( ) and assure( ) The
Page 756 and 757:
also from the insights of friends i
Page 758 and 759:
elationship where it doesn’t exis
Page 760 and 761:
22. Don’t use private inheritance
Page 762 and 763:
than global variables, although you
Page 764 and 765:
the heap, the catcher must know to
Page 766 and 767:
has enough information to deal with
Page 768 and 769:
768 Thinking in C++ www.BruceEckel.
Page 770 and 771:
C Thinking in C: Foundations for Ja
Page 772 and 773:
Analysis & Design Extreme Programmi
Page 774 and 775:
mathematical determinism and the il
Page 776 and 777:
# compiler under dos: { all } # Obj
Page 778 and 779:
C07:MemTest.cpp C09:Cpptime.cpp C12
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Index -, 177 --, 178 !, 177 !=, 172
Page 782 and 783:
linking compiled C code with C++, 4
Page 784 and 785:
declaration, 93, 245, 256 analyzing
Page 786 and 787:
static member, 378, 440, 477 using
Page 788 and 789:
Love, Tom, 777 lvalue, 170, 358 mac
Page 790 and 791:
organization code, 260 code in head
Page 792 and 793:
short, 145 side effect, 170, 178 si
Page 794 and 795:
assembly-language code generated by
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MindView Ad Space 796
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