= Bolt Tutorial, part II: Exercises =

Now let's add some exercises.
The first one is '''conifer_ex1.php''':
{{{
<?php
echo "Conifers are so named because:";
exclusive_choice(
    array(
        'They carry their seeds in cones',
        'They are cone-shaped',
        'They originated in the Coniceous era',
    )
);
?>
}}}
'''exclusive_choice()''' defines a multiple-choice question.

The exercises are added to the course file:
Then edit conifer.php:
{{{
function intro_exercises() {
    return exercise_set(
        name('Intro exercises'),
        number(2),
        exercise(
            filename('conifer_ex1.php')
        ),
        exercise(
            filename('conifer_ex2.php')
        ),
        repeat(.3, intro_lessons(), REVIEW),
        repeat(.7, intro_lessons(), REVIEW|REPEAT),
        repeat(1, null, REPEAT|NEXT),
        refresh(array(7, 14, 28))
    );
}

...

return sequence(
    name('course'),
    intro_lessons(),
    intro_exercises(),
    pine_lessons(),
    id_exercises()
);
}}}
Start the course from the beginning.
When you get to the exercise you'll see

[[Image(bolt_ex.jpg, nolink)]]

You'll then see either

[[Image(bolt_right.jpg, nolink)]]

or

[[Image(bolt_wrong.jpg, nolink)]]

depending on whether you answered the question correctly.


Some notes:
 * In '''exclusive_choice()''', the correct answer is always the first choice listed.  Bolt randomly reorders the choices to remove any ordering effects.
 * The exercise page is used to generate both the exercise and the answer page.
 * If you look at your course history, you'll see that Bolt has stored your answers to the exercise, and your score, in its database.

== Reviewing and repeating exercises ==

Suppose the student doesn't perform the exercise correctly,
and you want to let them (or require them to) review the lessons and repeat the exercise?
Bolt provides a powerful mechanism for this, called '''exercise sets'''.
To illustrate this, first let's create a new exercise, '''conifer_ex2.php''':
{{{
<?php
echo "
Check the correct statements.
";

inclusive_choice(array(
    array("Conifers drop their leaves in autumn", 0),
    array("All conifers have needle-like leaves", 0),
    array("Conifers carry their seeds in cones", 1)
));
?>
}}}

This exercise is a set of true/false questions; the 0/1 arguments indicate which are true.

Edit conifer.php to contain:
{{{
function both_lessons() {
    return sequence(
        name('both lessons'),
        lesson(
            name('Introduction'),
            filename('conifer_intro.php')
        ),
        lesson(
            name('Conifers and deciduous trees'),
            filename('conifer_decid.php')
        )
    );
}

function second_lesson() {
    return lesson(
        name('Conifers and deciduous trees'),
        filename('conifer_decid.php')
    );  
}

function exercises() {
    return exercise_set(
        name('exercise set 1'),
        number(2),
        exercise(
            filename('conifer_ex1.php')
        ),
        exercise(
            filename('conifer_ex2.php')
        ),
        repeat(.3, both_lessons(), REVIEW),
        repeat(.7, second_lesson(), REVIEW|REPEAT),
        repeat(1, null, REPEAT|NEXT),
        refresh(array(7, 14, 28))
    );
}

return sequence(
    name('course'),
    both_lessons(),
    exercises()
);

}}}


The course structure is now:

[[Image(xset.png, nolink)]]