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Discussion on: The vanilla Javascript basics to know before learning React JS

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maxdevjs profile image
maxdevjs • • Edited

@tracycss thank you for the great article :)

This snippet

//const object properties or array values can be updated
const friends = [{
    name: 'Bob 🥽',
    age: 22,
    hobby: 'golf🏌',
    music: 'rock 🎸'
  }

];

const result = friends.age = 23;
console.log(result);
//output => 23
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does not update the original age (I guess the code was intended to update age from 22 to 23, right?). Instead it creates a new named property of the array object:

console.log(friends);
[
  { name: 'Bob 🥽', age: 22, hobby: 'golf🏌', music: 'rock 🎸' },
  age: 23
]
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This can be checked:

// new (named) age property
console.log(friends.age);
23
// also
console.log(friends["age"]) ;
23

// original age
console.log(friends[0].age) ;
22
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To update the original age:

friends[0].age = 23;
console.log(friends[0].age) ;
23
// also
console.log(friends[0]["age"]) ;
23
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tracycss profile image
Jane Tracy 👩🏽‍💻 • • Edited

Great input Max, I might the values or properties can be changed. Let me update that part.
Thank you. 💯🌟🙂