Is nil pointer
Is nil pointer ( aPointer ) : Boolean
| Parameter | Type | Description | |
|---|---|---|---|
| aPointer | Pointer | → | Pointer to be tested |
| Function result | Boolean | ← | TRUE = Nil pointer (->[]) FALSE = Valid pointer to an existing object |
Description
The Is nil pointer command returns True if the pointer you pass in aPointer is Nil (->[]). It returns False in all other cases (pointer to field, table or variable).
If you want to find out the name of the variable or the number of the field that is being pointed to, you can use the RESOLVE POINTER command.
Example
var $ptr : Pointer
...
If(Is nil pointer($ptr))
End if
// is equivalent to
If($ptr=Null)
End if