// 设置数组
  const avengers = ['Tony Stark', 'Steve Rogers', 'Natasha Romanoff'];

  // 把数组解构赋值给变量。数组模式位于赋值运算符 `=` 的左侧，被结构的数组在
  // 其右侧。
  const [ironMan, cap, blackWidow] = avengers;

  // ironMan = 'Tony Stark' 
  // cap = 'Steve Rogers'
  // blackWidow = 'Natasha Romanoff'

  // 输出 ironMan:
  ironMan;

 const avengers = ['Tony Stark', 'Steve Rogers', 'Natasha Romanoff'];

  // 我们不用用到Tony
  const [, cap, blackWidow] = avengers;

  // ironMan = Error: undefined 
  // cap = 'Steve Rogers'
  // blackWidow = 'Natasha Romanoff'

  // 输出 cap:
  cap;

 const avengers = ['Tony Stark', 'Steve Rogers', 'Natasha Romanoff'];

  // cap 缺失
  const [ironMan, , blackWidow] = avengers;

  // ironMan = 'Tony Stark' 
  // cap = Error: undefined
  // blackWidow = 'Natasha Romanoff'

  // 输出 blackWidow:
  blackWidow;

 const avengers = ['Tony Stark', 'Steve Rogers', 'Natasha Romanoff'];

  // ironMan vs cap
  const [ironMan, cap] = avengers;

  // ironMan = 'Tony Stark' 
  // cap = 'Steve Rogers'
  // blackWidow = Error: undefined

  // 输出 blackWidow:
  ironMan;

 // Destructuring Nested Arrays
  const avengers = [
            'Natasha Romanoff', 
            ['Tony Stark', 'James Rhodes'], 
            ['Steve Rogers', 'Sam Wilson']
          ];

  // Avengers and their partners
  const [blackWidow, [ironMan, warMachine], [cap, falcon]] = avengers;

  // blackWidow = 'Natasha Romanoff'
  // ironMan = 'Tony Stark'
  // warMachine = 'James Rhodes'
  // cap = 'Steve Rogers'
  // falcon = 'Sam Wilson'

  // Output warMachine:
  warMachine;

 // 从该数组中提取 Pepper Potts
  const avengers = [
            'Natasha Romanoff', 
            [['Tony Stark', 'Pepper Potts'], 'James Rhodes'], 
            ['Steve Rogers', 'Sam Wilson']
          ];

  // Destructure
  const [ , // 跳过 'Natasha Romanoff'
       [[ , // 跳过 'Tony Stark'
       hera // Pepper Potts 赋值给变量 'hera'
     ]]] = avengers;

  // 请注意：你也可以这样写
  // const [, [[, hera ]]] = avengers;

  // 输出 hera:
  hera;

  // hera = 'Pepper Potts'

 // 通过rest操作符解构
  const avengers = ['Natasha Romanoff', 'Tony Stark', 'Steve Rogers'];

  const [blackWidow, ...theOthers] = avengers;

  theOthers;
  // blackWidow = 'Natasha Romanoff'
  // theOthers = ['Tony Stark', 'Steve Rogers']

  // 输出 theOthers:
  theOthers;

 //解构对象的属性值，赋给单个变量 `a`:
 const { ironMan: a } = { ironMan: 'Tony Stark' };

 // 输出 a:
 a;  // a = 'Tony Stark '

 // Setup our object
 const avengers = {
  ironMan: 'Tony Stark', 
  cap: 'Steve Rogers', 
  blackWidow: 'Natasha Romanoff'
 };

 // Destructure object to individual variables
 const { 
  ironMan: a, 
  cap: b, 
  blackWidow: c 
 } = avengers;

 // a = 'Tony Stark '
 // b = 'Steve Rogers'
 // c ='Natasha Romanoff'

 // Output a:
 a;

 // Setup our object
 const avengers = {
  blackWidow: 'Natasha Romanoff',
  ironManCharacters: {
   couple: {
    ironMan: 'Tony Stark', 
    hera: 'Pepper Potts',
    },
    partner: {
       warMachine: 'James Brodie'
    }
  },
  capCharacters: {
   cap: 'Steve Rogers', 
   partner: {
    falcon: 'Sam Wilson'
   }
  }
 };

 // Destructure object to individual variables
 const { 
  blackWidow: a,
  ironManCharacters: { 
   couple: {
    ironMan: b,
    hera: c
  },
   partner: {
    warMachine: d
   }
  },
  capCharacters: {
   cap: e,
   partner: {
    falcon: f
   }
  }
 } = avengers;

 // a = 'Natasha Romanoff'
 // b = 'Tony Stark '
 // c = 'Pepper Potts'
 // d = 'James Brodie'
 // e = 'Steve Rogers'
 // f = 'Sam Wilson'

 // Output a:
 a;

 // Setup our object
 const avengers = {
  ironMan: 'Tony Stark', 
  cap: 'Steve Rogers', 
  blackWidow: 'Natasha Romanoff'
 };

 // Destructure object to individual variables with meaningful names
 const { 
  ironMan: ironMan,
  cap: cap, 
  blackWidow: blackWidow
 } = avengers;

 // blackWidow = 'Natasha Romanoff'
 // ironMan = 'Tony Stark '
 // cap = 'Steve Rogers'

 // Output blackWidow:
 blackWidow;

 // Setup our object
 const avenger = {
  ironMan: 'Tony Stark'
 };

 // Destructure object to individual variables with meaningful names
 const { 
  ironMan  // equivalent to 'ironMan: ironMan'
 } = avenger;

 // ironMan = 'Tony Stark '

 // Output ironMan:
 ironMan;

 // Setup our object
 const avengers = {
  ironMan: 'Tony Stark', 
  cap: 'Steve Rogers', 
  blackWidow: 'Natasha Romanoff'
 };

 // Destructure object to individual variables with meaningful names
 const { ironMan, cap, blackWidow } = avengers;

 // Output ironMan:
 ironMan;

 // Setup our object
const avengers = {
  blackWidow: 'Natasha Romanoff',
  ironManCharacters: {
   couple: {
     ironMan: 'Tony Stark',
     hera: 'Pepper Potts',
   },
   partner: {
     warMachine: 'James Brodie'
   }
  },
  capCharacters: {
   cap: 'Steve Rogers',
   partner: {
     falcon: 'Sam Wilson'
   }
  }
};

// Destructure a deeply nested object
const { ironManCharacters: { couple } } = avengers;

// couple = {
//  ironMan: 'Tony Stark', 
//  hera: 'Pepper Potts',
// }

// Output couple:
couple;

 const avengers = {
  ironManCharacters: {
   couple: {
     ironMan: 'Tony Stark', 
     hera: 'Pepper Potts',
   }
  }
};

const { 
  ironManCharacters: { 
   couple 
  }
} = avengers;

// Output couple:
couple;

const { 
  ironManCharacters: { 
   couple: couple
  }
} = avengers;

 const avengers = {
 blackWidow: 'Natasha Romanoff',
 ironManCharacters: {
  couple: {
   ironMan: 'Tony Stark',
   hera: 'Pepper Potts'
  }
 }
};

const ironManProperties = {
 family: {}
};

({
 ironManCharacters: {
  couple: ironManProperties.family
 }
} = avengers);

ironManProperties.family
// ironManProperties.family = {
//  ironMan: 'Tony Stark',
//  hera: 'Pepper Potts'
// }

// Output ironManProperties.family:
ironManProperties.family;

 // Setup our object
 const avengers = {
  ironMan: 'Tony Stark', 
  cap: 'Steve Rogers', 
  blackWidow: 'Natasha Romanoff'
 };

 // Destructure using defaults
 const { ironMan, cap, blackWidow, theHulk='Bruce Banner' } = avengers;

 // ironMan = 'Tony Stark' 
 // cap = 'Steve Rogers'
 // blackWidow = 'Natasha Romanoff'
 // theHulk = 'Bruce Banner'

 // Output blackWidow:
 blackWidow;

 // Setup our object
  const avengers = {
   ironMan: 'Tony Stark', 
   cap: 'Steve Rogers', 
   blackWidow: 'Natasha Romanoff',
   theHulk: 'Bruce Banner'
  };

  // Valid destructuring
  const { ironMan } = avengers;

  let { cap } = avengers;

  var { blackWidow } = avengers;

  // Invalid destructuring
  let theHulk;

  { theHulk } = avengers;
  // Error

  // Output theHulk:
  theHulk;

 // Setup our object
  const avengers = {
   ironMan: 'Tony Stark', 
   cap: 'Steve Rogers', 
   blackWidow: 'Natasha Romanoff',
   theHulk: 'Bruce Banner'
  };

  // A valid Hulk
  let theHulk;

  ({ theHulk } = avengers);
  // theHulk = 'Bruce Banner'

  // Output theHulk:
  theHulk;

 // Note: this doesn't work!
 function getTonyStark(avengers){
  return { ironMan: { realName } } = avengers;
  // return the avengers object, not the realName value
 }

 const avengers = {
  ironMan: {
   realName: 'Tony Stark'
  }
 };

 const tonyStark = getTonyStark(avengers);

 // tonyStark = {
 //  ironMan: {
 //   realName: 'Tony Stark'
 //  }
 // };

 // Output tonyStark:
 tonyStark;

 // Note: this DOES work!
 function getTonyStark(avengers){
  const { ironMan: { realName } } = avengers;
  return realName;
 }

 const avengers = {
  ironMan: {
   realName: 'Tony Stark'
  }
 };

 const tonyStark = getTonyStark(avengers);

 // tonyStark = 'Tony Stark'

 // Output tonyStark:
 tonyStark;

 function getTonyStark(avengers){
  return ({ ironMan: { realName } } = avengers) && realName;
 }

 const avengers = {
  ironMan: {
   realName: 'Tony Stark'
  }
 };

 const tonyStark = getTonyStark(avengers);
 // tonyStark = 'Tony Stark'

 // Output tonyStark:
 tonyStark;