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JavaScript: Data aggregation (strings)

You can use aggregation with strings as well as with numbers. In most cases, this applies to dynamic string generation, where you don't know in advance what size the string will be and what it will contain.

Imagine a function "multiplying" a string, that is, repeating a string a given number of times:

repeat('hexlet', 3); // 'hexlethexlethexlet'

The core mechanism of this function is simple, the loop "increments" the string a given number of times:

const repeat = (text, times) => {
  // A neutral element in terms of strings is an empty string
  let result = '';
  let i = 1;

  while (i <= times) {
    // Add a string on each iteration
    result = `${result}${text}`;
    i = i + 1;

  return result;

Break down the code's execution into steps:

// Calling repeat('hexlet', 3);
let result = '';
result = `${result}hexlet`; // hexlet
result = `${result}hexlet`; // hexlethexlet
result = `${result}hexlet`; // hexlethexlethexlet


Write the joinNumbersFromRange() function that joins all numbers in a range into a string:

joinNumbersFromRange(1, 1); // '1'
joinNumbersFromRange(2, 3); // '23'
joinNumbersFromRange(5, 10); // '5678910'
The exercise doesn't pass checking. What to do? 😶

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In my environment the code works, but not here 🤨

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My code is different from the teacher's one 🤔

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