NULL Type in NCL Programming
The NULL type is used where data in a component either must be null (that is, empty), or not accessible.
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The NULL type is used where data in a component either must be null (that is, empty), or not accessible.
- External Form - Input
- The only valid input is a null value.
- External Form - Output
- A null value is always returned.
- Local Form and Behavior
- The component can be created by an input operation, but no contents are modified. If it already exists no data is modified.