References
| Description | Properties | Functions | Examples | See also |
Any variable or object can be made to refer to another variable or object of the same type. A reference is created and destroyed using the method setreference.
Any object can be a reference. No special declaration is necessary.
While an object is a reference, reading or setting its value or properties, or calls to its methods are redirected to the referenced object.
After a reference is destroyed, the behavior of the object returns back to normal.
A reference is useful in situations when the actual object is not know a priori, only its type.
| r = isreference; |
| setreference(refobj); |
The argument refobj must be of the same type. If no argument is given, the reference is removed.
When a variable refers to another variable, calling its methods or properties and reading or writing its value always apply to the variable referenced.
An element of a vars or pars can be referenced, while an element of an array cannot.
Since the KPL language currently doesn't allow constructs such as MyVar[Index1, Index2].method,
a reference can be used to call the methods of individual elements of multidimensional variables.
For example, the following construct:
RefVar.setreference(MulVar[0, 1]);
RefVar.loadfromfile(FileName);
RefVar.setrefrence;
will load data from file into MulVar[0, 1].