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C++ Language/Objects/Inheritance/PolymorphismSyntax

< C++ Language | Objects | Inheritance
C++ Language
  1. Overview
  2. Preprocessing
    1. Macros
    2. Tokenization
    3. Preprocessing Strings
    4. Compile-time Constants
    5. Compile-time Assertions
    6. Conditional-Compilation
  3. Namespace
    1. Namespace Shortcuts
    2. Nesting
    3. Splitting across Files
    4. Named and Unnamed
  4. Type
    1. Hungarian Prefixes
    2. Boolean
    3. Literals
    4. Bitwise Representation
    5. Max Value
    6. Conversion
    7. Enumeration
    8. Shortcuts
    9. Variant
    10. RTTI: RunTime Type Information
  5. Variables
    1. Lifetime and Scope
    2. Initialization
    3. Uniform Initialization
    4. Initialize without Constructor
    5. Decomposing-Auto
    6. Define at Same Time as Type
  6. Indirection
    1. Pointers
    2. Typed NULL
    3. Arrays
    4. Reference Variables
    5. Rvalue-References
    6. Smart Pointers
  7. Expressions
    1. Precedence
    2. Chain of Assignment
  8. Program Flow
    1. Loops
    2. The break Statement
    3. Return Value
    4. Parameters
    5. Function Overloading
    6. Function-Pointer
    7. Deprecating a Function
  9. Objects
    1. Accessibility
    2. Unwanted Compiler-Generated Functions
    3. Constructors
    4. Destructors
    5. Const Members
    6. Static Members
    7. Inheritance
    8. Operator Overloading
    9. Nested Classes
    10. Pointer to Members
    11. Low-Level C Structures
  10. Templates
    1. Templated-Functions
    2. Templated-Classes
    3. Templated-Variables
    4. Template-Parameters
    5. Traits
    6. Metaprogramming
    7. Concepts
  11. Error Handling
    1. Returning an Error Code
    2. Assertions
    3. C++ Exception Handling
  12. Standard Libraries
    1. C-Runtime
    2. STL: Standard Template Library
    3. Strings
    4. IOStreams
    5. Filesystem Access
    6. Multithreading
    7. RNG: Random Number Generator
  13. Obsolete Features

Frequently, an object is allocated by instantiating the derived class, but "pointed-at" by a pointer variable whose type is "pointer-to-base-class": CRBase* poBase = (CRBase*)(new CRDerived);. If CRBase and CRDerived have provided two different implementations of the same DoAction() member function, then poBase->DoAction() would call the base class' implementation. But if the member function had been marked by the virtual keyword, then poBase->DoAction() would instead "polymorphically" call the derived class' implementation.

Additional information about polymorphism syntax

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