References

An alias for a variable

 

Utilises the ampersand & symbol

 

Syntax:    int & myAlias = myVar ;  //now myAlias and myVar are effectively the same

 

Any changes to the reference are reflected in the original, and vice-versa.

 

References are similar to pointers, but do not work under the principles of 'address of' or dereferencing.

 

  • alias for a variable
  • when declaring must be initialised to a variable
  • cannot have NULL references
  • data type (primitive or abstract) must precede the ampersand &
    • dataType & alias

This example assigns two references and also shows references being passed into a function:

Compile & Run:

a before swap: 17
b before swap: 42
a after swap: 42
b after swap: 17

 


*Note: Maybe slightly confusing with respect to the ampersand & symbol also being used as the 'address of' operator. The thing to remember with references is that they should always be initialised to an existing variable.

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