join<R>  method 
      
  
R
join<R>( 
    
    
- R mapFirst(
- A
 
 - R mapSecond(
- B
 
 - R mapThird(
- C
 
 - R mapFourth(
- D
 
 - R mapFifth(
- E
 
 - R mapSixth(
- F
 
 - R mapSeventh(
- G
 
 - R mapEighth(
- H
 
 
override
    Implementation
@override
R join<R>(
  R Function(A) mapFirst,
  R Function(B) mapSecond,
  R Function(C) mapThird,
  R Function(D) mapFourth,
  R Function(E) mapFifth,
  R Function(F) mapSixth,
  R Function(G) mapSeventh,
  R Function(H) mapEighth,
) {
  return mapFifth(_value);
}