Like any other language, JavaScript comes with a set of useful functions. All together they make up the so-called standard library. It usually contains thousands of functions you can't remember, and you don't have to. It is assumed that any programmer knows where to look for their documentation and has a rough idea of what they want to achieve. And the rest is a matter of technique. Without the Internet, most programmers wouldn't be able to program anything.
To newcomers, it often looks like this: "Go I know not whither and fetch I know not what". In other words, most people have no idea how to learn about these functions when they don't know anything at all. Oddly enough, there is no way to know everything you need to know once and for all. As you grow as a developer, you learn all the exciting features that solve your problems more elegantly, thus expanding your toolbox.
Here are some tips to learn about new features:
The JavaScript standard library's structure has its peculiarities. Since the code can run in different environments, such as a server or a browser, the capabilities of the standard library are highly dependent on the use case. For example, you can't perform some server tasks in a browser. For server-side documentation, see https://nodejs.org. The server portions of the standard library are organized into modules, each module has its own page with full descriptions of all its functions. In particular, the module fs is required to work with the file system, its functions allow you to write and read files.
As for the browsers, there's not much stuff. For the most part, it's some basic functions built into the language. For example, the math functions we've seen before.. The rest of the features you can add via third-party libraries.
The typeof operator defines the type of the operand. The type name returns as a string. For example, calling typeof 'go go go' will return the string 'string'.
console.log(typeof 3); // => 'number'
Print the type of the value of the constant motto.
If you've reached a deadlock it's time to ask your question in the «Discussions». How ask a question correctly:
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.
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.
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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Standard library is a set of useful features bundled in the programming language.