a higher order function - sums the results of two other functions , passed to it as parameters . concode_field_sep PlaceHolder placeHolder concode_field_sep int chapter concode_elem_sep String name concode_elem_sep Function<String,String> greet concode_elem_sep void run concode_elem_sep void main
int function ( Function < T , Integer > arg0 , Function < R , Integer > arg1 , T arg2 , R arg3 ) { return arg0 . apply ( arg2 ) + arg1 . apply ( arg3 ) ; }