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Add Key Value Pair To All Objects In Array

Are you looking to enhance your coding skills and level up your programming game? If so, you've come to the right place!

Today, we're going to dive into a common scenario in software development - adding a key-value pair to all objects in an array. This is a handy trick that you'll encounter frequently when working with arrays of objects in JavaScript, Python, or other programming languages.

Let's start by breaking down the problem. You have an array of objects, and you want to add a new key-value pair to each object in the array. This can be incredibly useful in many real-world applications, such as adding metadata to a list of items or updating data structures efficiently.

To tackle this task, we'll need to iterate through each object in the array and append the desired key-value pair to it. Let's walk through a step-by-step guide on how to accomplish this in JavaScript:

Javascript

// Sample array of objects
const people = [
  { name: 'Alice', age: 30 },
  { name: 'Bob', age: 25 },
  { name: 'Charlie', age: 35 }
];

// Adding a new key-value pair to all objects in the array
const updatedPeople = people.map(person => ({
  ...person,
  newKey: 'newValue'
}));

console.log(updatedPeople);

In the code snippet above, we start with an array called `people` containing several objects. We use the `map()` method to iterate through each object and create a new object with the existing properties spread using the spread operator `...person`, along with the new key-value pair `newKey: 'newValue'`.

By running this code, you'll see the updated array `updatedPeople` where each object now includes the additional key-value pair. This is an elegant and concise way to achieve our goal without mutating the original objects.

If you're working with Python, a similar approach can be applied using list comprehension. Here's how you can add a key-value pair to all dictionaries in a list:

Python

# Sample list of dictionaries
people = [
    {'name': 'Alice', 'age': 30},
    {'name': 'Bob', 'age': 25},
    {'name': 'Charlie', 'age': 35}
]

# Adding a new key-value pair to all dictionaries in the list
updated_people = [{**person, 'newKey': 'newValue'} for person in people]

print(updated_people)

In Python, we use a list comprehension to accomplish the task. By iterating through each dictionary and merging it with a new dictionary containing the additional key-value pair, we effectively update all dictionaries in the original list.

By mastering this technique, you'll have a powerful tool in your coding arsenal to efficiently manipulate arrays of objects. Whether you're a beginner or seasoned developer, adding key-value pairs to all objects in an array is a fundamental skill that will undoubtedly come in handy in your software engineering journey. Happy coding!