bovine: Order of components in rules

 
 2.3 Order of components in rules
 ================================
 
 If a rule has multiple components, order is important, for example
 
      headerfile : symbol PERIOD symbol
                 | symbol
                 ;
 
    would match ‘foo.h’ or the C++ header ‘foo’.  The bovine parser will
 first attempt to match the long form, and then the short form.  If they
 were in reverse order, then the long form would never be tested.