copy method

(T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13) copy({
  1. T1? $1,
  2. T2? $2,
  3. T3? $3,
  4. T4? $4,
  5. T5? $5,
  6. T6? $6,
  7. T7? $7,
  8. T8? $8,
  9. T9? $9,
  10. T10? $10,
  11. T11? $11,
  12. T12? $12,
  13. T13? $13,
})

Implementation

(T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13) copy({
  T1? $1,
  T2? $2,
  T3? $3,
  T4? $4,
  T5? $5,
  T6? $6,
  T7? $7,
  T8? $8,
  T9? $9,
  T10? $10,
  T11? $11,
  T12? $12,
  T13? $13,
}) => (
  $1 ?? this.$1,
  $2 ?? this.$2,
  $3 ?? this.$3,
  $4 ?? this.$4,
  $5 ?? this.$5,
  $6 ?? this.$6,
  $7 ?? this.$7,
  $8 ?? this.$8,
  $9 ?? this.$9,
  $10 ?? this.$10,
  $11 ?? this.$11,
  $12 ?? this.$12,
  $13 ?? this.$13,
);