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C++ Language/Variables/InitializeWithoutConstructor

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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
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    2. The break Statement
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    6. Function-Pointer
    7. Deprecating a Function
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    8. Operator Overloading
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    10. Pointer to Members
    11. Low-Level C Structures
  10. Templates
    1. Templated-Functions
    2. Templated-Classes
    3. Templated-Variables
    4. Template-Parameters
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  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

Traditionally, data members were initialized by passing parameters to a custom constructor, which would copy those parameterized values to the data members.

In modern C++, you also have the option of just using the default constructor, and specifying those values as an initialization list. The items from that brace-enclosed list will be given to data members based on the order of members within the class definition.

Additional information about initializing without a constructor (includes interactive examples)

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