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QxtNullable< T > Class Template Reference
[Core]

distinct null value compatible with any data type. More...

Public Member Functions

• QxtNullable (QxNullableNull)
• QxtNullable (const T &p)
• bool isNull () const

  determinates if the Value is set to something meaningfull
  

• void nullify ()

  delete Value
  

• T & value () const
• operator T () const
• void operator= (const T &p)

Related Functions

(Note that these are not member functions.)

• qxtNull(t, n)

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Detailed Description

template<typename T>
class QxtNullable< T >

distinct null value compatible with any data type.

in general it's a templated abstraction to allow any data type to be expressed with a null value distinct from any real value.

you can use it for skipable arguments.
prepare a function for argument skipping:

void  somefunction( qxtNull(int,a) , qxtNull(int,b) )
{
 
if (!a.isNull())
        {
        int i = a.value();
        //do something with i
        }
 if (!b.isNull())
        {
        int x = b.value();
        //do something with x
        }
}

usage:

somefunction(SKIP,1,2);
somefunction(3,4);
somefunction(3,SKIP,6);
somefunction(1);

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Friends And Related Function Documentation

template<typename T>

qxtNull ( t, n  ) [related]

defines a skipable argument with type t and variable name n