Logical Existence Functoid
Use the Logical Existence functoid ( 
) to determine whether the Record, Field Element, or Field Attribute node that is linked to it exists in a particular input instance message.
Parameter 1: A link from a Record, Field Element, or Field Attribute node in the source schema that may or may not exist in a particular input instance message.
Output 1: The Boolean value True if the element or attribute that corresponds to the Record, Field Element, or Field Attribute node that is linked to this functoid exists in a particular input instance message; the Boolean value False otherwise.
The node in the source schema to which this functoid is linked must be a node that corresponds to an actual element or attribute in an instance message.
