深拷贝

https://stackoverflow.com/questions/21744480/clone-a-list-map-or-set-in-dart

2

For lists and sets, I typically use

List<String> clone = []..addAll(originalList);

The caveat, as @kzhdev mentions, is that addAll() and from()

[Do] not really make a clone. They add a reference in the new Map/List/Set.

That's usually ok with me, but I would keep it in mind.

=======================================================================================================

This solution should work:

List list1 = [1,2,3,4];

List list2 = list1.map((element)=>element).toList();

It's for a list but should work the same for a map etc, remember to add to list if its a list at the end

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LIst 多层情况下的addall, map表现, (无效); 还是循环到最底层生效了...

import 'dart:io';
import 'dart:convert';
import 'dart:math';

main(){
  List startList = [];
  startList.addAll(spareParts[Random().nextInt(7)]);

  print(startList);
  startList[0][0] = 999;
  print(';;;;;;;;;;;;;;;');
  print('startList $startList');
  print('spareParts $spareParts');

  List ddd = startList.map((v)=>v).toList();
  print('ddd: $ddd');
  ddd[0][0] = 88888;
  print('mmmmmmmmmmmmmmmmmmmmmmmmmmmmmm');
  print('ddd: $ddd');
  print('startList $startList');
  print('spareParts $spareParts');
  print('mmmmmmmmmmmmmmmmmmmmmmmmmmmmmm');
  ddd = [[],[],[],[]];
  for(int y=0; y<4; y++){
    for(int x=0; x<4; x++){
      ddd[y].add(startList[y][x]);
    }
  }

  print('ddd$ddd');
  print('startList $startList');
  print('mmmmmmmmmmmmmmmmmmmmmmmmmmmmmm');
  ddd[0][0] = 555555555;


  print('ddd$ddd');
  print('startList $startList');
  print('mmmmmmmmmmmmmmmmmmmmmmmmmmmmmm');
}


List spareParts = [
  [[0,1,0,0],
  [0,1,0,0],
  [0,1,0,0],
  [0,1,0,0]],

  [[0,0,0,0],
  [0,1,0,0],
  [1,1,1,0],
  [0,0,0,0]],

  [[0,0,0,0],
  [1,1,1,0],
  [0,0,1,0],
  [0,0,0,0]],

  [[0,0,0,0],
  [0,1,1,1],
  [0,1,0,0],
  [0,0,0,0]],

  [[0,0,0,0],
  [1,1,0,0],
  [0,1,1,0],
  [0,0,0,0]],

  [[0,0,0,0],
  [0,0,1,1],
  [0,1,1,0],
  [0,0,0,0]],

  [[0,0,0,0],
  [0,1,1,0],
  [0,1,1,0],
  [0,0,0,0]],
];

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