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Note : Attributes are evaluated in order, so Variables defined in an Attribute (or the attribute name itself) can be referenced in a later Attribute Expression, or in a dependent Expression that is referenced after that Attribute is evaluated.
E.g. you can refer in a pipe index Expression to a $variable if you have done a “lookup"lookup($variable)� " in the Stream before that pipe reference (or in an Output Multiplier, or an Output Filter), but otherwise you can’t.
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