USAGE:
     SWITCH value cases /default case
DESCRIPTION:
     Selects a choice and evaluates what follows it.
     SWITCH is a function.
ARGUMENTS:
     value -- Value to search for. (Type: any)
     cases -- Block of cases to search. (Type: block)
REFINEMENTS:
     /default
         case -- Default case if no others are found. (Type: any)

Example 1: Help lines in REBOL.