ByRef

```
@Documented
@Retention(RUNTIME)
@Target({METHOD,PARAMETER})
public @interface ByRef
```
Indicates that an argument gets passed or returned by reference. When used alongside FunctionPointer, the Generator passes the underlying C++ function object (aka functor) instead of a function pointer.

See Also:

Generator

Optional Element Summary

Optional Elements
Modifier and Type	Optional Element	Description
`java.lang.String`	`nullValue`	A C++ expression to use when null is passed.
`boolean`	`value`	When true indicates that the argument actually needs to be an rvalue reference (aka movable value).

- Element Detail
  - value
```
boolean value
```
    When true indicates that the argument actually needs to be an rvalue reference (aka movable value).
    
    Default:
    
    false
- - nullValue
```
java.lang.String nullValue
```
    A C++ expression to use when null is passed. By default NullPointerException is thrown.
    
    Default:
    
    ""