the processes thus for example the statement in the first line of the embodiment of fig1 means that the combined u201c casting machining u201d process routing consists of performing the casting process followed by performing the machining process in the second line the process of casting is further defined with reference to its sub processes namely that is the process of casting consists a choice between either performing sandcasting or performing diecasting continuing through the routing template specification of fig1 each process is defined recursively with reference to its sub processes if any in the syntax of fig1 square brackets around a process signifies an optional process routing alternatives can be marked as non auto selectable or u201c user only u201d by preceding the alternative with u2225 for example in the following template snippet the manual floor alternative has been marked as user only a user only alternative is presented like a standard alternative in a routing editor however in auto select mode it is ignored by the cost engine and thus will only be costed if the user explicitly selects it the primary use for this feature is to speed up auto costing by limiting the number of alternatives that are considered it also provides a natural way to include alternatives that are only intended to be used when explicitly indicated by the user a template can reference a node defined in another process group this is referred to as an.