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C++ Gotchas: Avoiding Common Problems in Coding and Design
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Table of content
Copyright
Addison-Wesley Professional Computing Series
Preface
Acknowledgments
Chapter 1. Basics
Gotcha #1: Excessive Commenting
Gotcha #2: Magic Numbers
Gotcha #3: Global Variables
Gotcha #4: Failure to Distinguish Overloading from Default Initialization
Gotcha #5: Misunderstanding References
Gotcha #6: Misunderstanding Const
Gotcha #7: Ignorance of Base Language Subtleties
Gotcha #8: Failure to Distinguish Access and Visibility
Gotcha #9: Using Bad Language
Gotcha #10: Ignorance of Idiom
Gotcha #11: Unnecessary Cleverness
Gotcha #12: Adolescent Behavior
Chapter 2. Syntax
Gotcha #13: Array/Initializer Confusion
Gotcha #14: Evaluation Order Indecision
Gotcha #15: Precedence Problems
Gotcha #16: 'for' Statement Debacle
Gotcha #17: Maximal Munch Problems
Gotcha #18: Creative Declaration-Specifier Ordering
Gotcha #19: Function/Object Ambiguity
Gotcha #20: Migrating Type-Qualifiers
Gotcha #21: Self-Initialization
Gotcha #22: Static and Extern Types
Gotcha #23: Operator Function Lookup Anomaly
Gotcha #24: Operator '->' Subtleties
Chapter 3. The Preprocessor
Gotcha #25: '#define' Literals
Gotcha #26: '#define' Pseudofunctions
Gotcha #27: Overuse of '#if'
Gotcha #28: Side Effects in Assertions
Chapter 4. Conversions
Gotcha #29: Converting through 'void *'
Gotcha #30: Slicing
Gotcha #31: Misunderstanding Pointer-to-Const Conversion
Gotcha #32: Misunderstanding Pointer-to-Pointer-to-Const Conversion
Gotcha #33: Misunderstanding Pointer-to-Pointer-to-Base Conversion
Gotcha #34: Pointer-to-Multidimensional-Array Problems
Gotcha #35: Unchecked Downcasting
Gotcha #36: Misusing Conversion Operators
Gotcha #37: Unintended Constructor Conversion
Gotcha #38: Casting under Multiple Inheritance
Gotcha #39: Casting Incomplete Types
Gotcha #40: Old-Style Casts
Gotcha #41: Static Casts
Gotcha #42: Temporary Initialization of Formal Arguments
Gotcha #43: Temporary Lifetime
Gotcha #44: References and Temporaries
Gotcha #45: Ambiguity Failure of 'dynamic_cast'
Gotcha #46: Misunderstanding Contravariance
Chapter 5. Initialization
Gotcha #47: Assignment/Initialization Confusion
Gotcha #48: Improperly Scoped Variables
Gotcha #49: Failure to Appreciate C++'s Fixation on Copy Operations
Gotcha #50: Bitwise Copy of Class Objects
Gotcha #51: Confusing Initialization and Assignment in Constructors
Gotcha #52: Inconsistent Ordering of the Member Initialization List
Gotcha #53: Virtual Base Default Initialization
Gotcha #54: Copy Constructor Base Initialization
Gotcha #55: Runtime Static Initialization Order
Gotcha #56: Direct versus Copy Initialization
Gotcha #57: Direct Argument Initialization
Gotcha #58: Ignorance of the Return Value Optimizations
Gotcha #59: Initializing a Static Member in a Constructor
Chapter 6. Memory and Resource Management
Gotcha #60: Failure to Distinguish Scalar and Array Allocation
Gotcha #61: Checking for Allocation Failure
Gotcha #62: Replacing Global New and Delete
Gotcha #63: Confusing Scope and Activation of Member 'new' and 'delete'
Gotcha #64: Throwing String Literals
Gotcha #65: Improper Exception Mechanics
Gotcha #66: Abusing Local Addresses
Gotcha #67: Failure to Employ Resource Acquisition Is Initialization
Gotcha #68: Improper Use of 'auto_ptr'
Chapter 7. Polymorphism
Gotcha #69: Type Codes
Gotcha #70: Nonvirtual Base Class Destructor
Gotcha #71: Hiding Nonvirtual Functions
Gotcha #72: Making Template Methods Too Flexible
Gotcha #73: Overloading Virtual Functions
Gotcha #74: Virtual Functions with Default Argument Initializers
Gotcha #75: Calling Virtual Functions in Constructors and Destructors
Gotcha #76: Virtual Assignment
Gotcha #77: Failure to Distinguish among Overloading, Overriding, and Hiding
Gotcha #78: Failure to Grok Virtual Functions and Overriding
Gotcha #79: Dominance Issues
Chapter 8. Class Design
Gotcha #80: Get/Set Interfaces
Gotcha #81: Const and Reference Data Members
Gotcha #82: Not Understanding the Meaning of Const Member Functions
Gotcha #83: Failure to Distinguish Aggregation and Acquaintance
Gotcha #84: Improper Operator Overloading
Gotcha #85: Precedence and Overloading
Gotcha #86: Friend versus Member Operators
Gotcha #87: Problems with Increment and Decrement
Gotcha #88: Misunderstanding Templated Copy Operations
Chapter 9. Hierarchy Design
Gotcha #89: Arrays of Class Objects
Gotcha #90: Improper Container Substitutability
Gotcha #91: Failure to Understand Protected Access
Gotcha #92: Public Inheritance for Code Reuse
Gotcha #93: Concrete Public Base Classes
Gotcha #94: Failure to Employ Degenerate Hierarchies
Gotcha #95: Overuse of Inheritance
Gotcha #96: Type-Based Control Structures
Gotcha #97: Cosmic Hierarchies
Gotcha #98: Asking Personal Questions of an Object
Gotcha #99: Capability Queries
Bibliography

Chapter 4. Conversions

C++'s type system is appropriately complex for a language of its expressive power. This base complexity is complicated further by the presence of user-defined conversions that may be applied implicitly during translation. In effect, the ability to extend the C++ language through the addition of abstract data types gives the designer the responsibility of designing an effective, safe, and coherent type system. Because C++ is largely statically typed, it should be possible to tame this complexity with effective design.

Unfortunately, poor coding practices can compromise even the most coherent designs. In this chapter, we'll look at some common practices that defeat static type safety. We'll also look at some frequently misunderstood areas of the C++ language that can result in compromised static type safety.