?? (LogiX node)
The ?? node outputs the value of the first input which is not null.
When spawned from the node browser, this node accepts the object datatype by default. However, this node can be overloaded to use various reference types if an appropriate wire is connected. Inputs are checked for not-null values in order: A, then B (or Operands., Operands., Operands. ... etc. if more than 2 inputs are present). Output will be null if all inputs are also null. This operator can be referred to as the 'null-coalescing' operator.