The OBJECT Get data source command returns the current data source of the object(s) designated by the object and * parameters.
You can define the data source for an object in Design mode using the Property List, or using the OBJECT SET DATA SOURCE command.
Passing the optional * parameter indicates that the object parameter is an object name (string). If you do not pass this parameter, it indicates that the object parameter is a field or variable. In this case, you pass a field or variable reference instead of a string (field or variable object only).
Given a combo box object defined in a form:
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You execute the following code:
$vPtr :=OBJECT Get data source(*;"vCombo")