22877eb0__Services___O_Reilly_Broadcast_Table_3__Command_Pipes_Command
[Description] A variable is a specific computed result or assignment. Variables can only be set by the XProc statement, though variables can be shadowed (a variable can be used in different scopes, having different values in those scopes). [Command] 
variable
XProc: Drupal, XML Pipelines and RESTful Services - O'Reilly Broadcast
Command