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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

Instructions

Write a function, joinNumbersFromRange(), which 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 🤨

Tests are designed so that they test the solution in different ways and against different data. Often the solution works with one kind of input data but doesn't work with others. Check the «Tests» tab to figure this out, you can find hints at the error output.

My code is different from the teacher's one 🤔

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