With this plugin, a book can contain interactive exercises (currently only in Javascript). An exercise is a code challenge provided to the reader, who is given a code editor to write a solution which is checked against the book author's validation code.

To use the exercises plugin in your Gitbook project, add the exercises plugin to the book.json file, then install plugins using gitbook install.

{
    "plugins": ["exercises"]
}

An exercise is defined by 4 simple parts:

• Exercise Message/Goals (in markdown/text)
• Initial code to show to the user, providing a starting point
• Solution code, being a correct solution to the exercise
• Validation code that tests the correctness of the user's input

{% exercise %}
Define a variable `x` equal to 10.
{% initial %}
var x =
{% solution %}
var x = 10;
{% validation %}
assert(x == 10);
{% context %}
// This is context code available everywhere
// The user will be able to call magicFunc in his code
function magicFunc() {
    return 3;
}
{% endexercise %}

The old format (gitbook < 2.0.0) is still supported but deprecated.