Is a variable

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4D v20 R7

4D Language Reference

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Is a variable


Is a variable ( aPointer ) -> Function result

Parameter	Type	Description
aPointer	Pointer	Pointer to be tested
Function result	Boolean	TRUE = Pointer points to a variable FALSE = Pointer does not point to a variable

Description

The Is a variable command returns True if the pointer you pass in aPointer references a defined variable. It returns False in all other cases (pointer to field or table, Nil pointer, and so on).

When you want to know the name of the variable being pointed to or the field number, you can use the RESOLVE POINTER command.