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JavaScript: Create an object from the given key-value pairs

JavaScript fundamental (ES6 Syntax): Exercise-41 with Solution

Write a JavaScript program to create an object from the given key-value pairs.

  • Use Array.prototype.reduce() to create and combine key-value pairs.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
const object_From_Pairs = arr => arr.reduce((a, v) => ((a[v[0]] = v[1]), a), {});
console.log(object_From_Pairs([['a', 1], ['b', 2]])); 
console.log(object_From_Pairs([[1, 10], [2, 20], [3, 30]]));

Sample Output:

{"a":1,"b":2}
{"1":10,"2":20,"3":30}

Pictorial Presentation:

JavaScript Fundamental: Create an object from the given key-value pairs

Flowchart:

flowchart: Create an object from the given key-value pairs

Live Demo:

See the Pen javascript-basic-exercise-1-41 by w3resource (@w3resource) on CodePen.


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Next: Write a JavaScript program to get a customized coalesce function that returns the first argument that returns true from the provided argument validation function.

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JavaScript: Tips of the Day

Chunks an array into n smaller arrays

Example:

const tips_chunkIntoN = (arr, n) => {
  const size = Math.ceil(arr.length / n);
  return Array.from({ length: n }, (v, i) =>
    arr.slice(i * size, i * size + size)
  );
}
console.log(tips_chunkIntoN([1, 2, 3, 4, 5, 6, 7,8], 4)); 

Output:

[[1,2],[3,4],[5,6],[7,8]]