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JavaScript: else

Let's write a function getTypeOfSentence() to analyze a piece of text and return its type: General sentence for normal sentences and Question sentence for questions.

  getTypeOfSentence('Hodor');  // General sentence
  getTypeOfSentence('Hodor?'); // Question sentence

Implementation:

const getTypeOfSentence = (sentence) => {
  // Declare a variable to store the sentence type
  let sentenceType;
  // Predicate checking the text ending
  // If it ends with '?', it will return true,
  // otherwise, it'll return false
  if (sentence.endsWith('?')) {
    // If the condition above holds true,
    // we have a question sentence.
    // Assign an appropriate value to sentenceType
    sentenceType = 'Question';
  } else {
    // Otherwise, the sentenceType is 'General'
    sentenceType = 'General';
  }

  // Build a string via interpolation
  return `${sentenceType} sentence`;
};

We have added the keyword else and a new block with curly brackets. This block executes only if the condition in if is false.

There are two ways to design an if-else clause. The negation allows you to change the order of the blocks:

const getTypeOfSentence = (sentence) => {
  let sentenceType;
  // Add negation
  // The code blocks with the 'else' and 'if' statements are swapped
  if (!sentence.endsWith('?')) {
    sentenceType = 'General';
  } else {
    sentenceType = 'Question';
  }

  return `${sentenceType} sentence`;
};

Which way is preferable? It is easier for the human brain to reason in a straightforward manner rather than via negation. Try to pick a test that has no negations, and then modify the contents of the code blocks to suit it.

Instructions

Write the normalizeUrl() function that carries out so-called data normalization. It takes a site address and returns it with https:// at the beginning.

The function accepts URLs both as URL or https://URL, but will always return it as https://URL

You can use a method, startsWith(), to check if the string starts with the prefix https://. And then add or don't add https:// accordingly.

Examples:

normalizeUrl("google.com"); // "https://google.com"
normalizeUrl("https://ai.fi"); // "https://ai.fi"
The exercise doesn't pass checking. What to do? 😶

If you've reached a deadlock it's time to ask your question in the «Discussions». How ask a question correctly:

  • Be sure to attach the test output, without it it's almost impossible to figure out what went wrong, even if you show your code. It's complicated for developers to execute code in their heads, but having a mistake before their eyes most probably will be helpful.
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 🤔

It's fine. 🙆 One task in programming can be solved in many different ways. If your code passed all tests, it complies with the task conditions.

In some rare cases, the solution may be adjusted to the tests, but this can be seen immediately.

I've read the lessons but nothing is clear 🙄

It's hard to make educational materials that will suit everyone. We do our best but there is always something to improve. If you see a material that is not clear to you, describe the problem in “Discussions”. It will be great if you'll write unclear points in the question form. Usually, we need a few days for corrections.

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Definitions

  • else - is a way to define a block of code that executes if the if condition is not satisfied


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