9.2. api.wml - the code

<:{
use vars qw(@question_number);

@question_number=(0);
}:>

;;; Perl code here:
<define-tag next-question><:{
    my $temp = pop(@question_number)+1;
    push @question_number, $temp;
    my $qn_text = join(".", @question_number);
    print $qn_text;
}:></define-tag>

;;; Perl code here:
<define-tag promote><:{
    push @question_number, 0;
}:></define-tag>

;;; Perl code here:
<define-tag demote><:{
    pop(@question_number);
}:></define-tag>



<define-tag question endtag="required">
;;; Define anchor to be the first argument
<preserve anchor />
;;; Define title to be the second argument
<preserve title />

;;; This statement is required to actually set
;;; anchor and title to a proper value
<set-var %attributes />

;;; next-question is defined above
<set-var question-number="<next-question />" />

<if <get-var render-body />
;;; If the question should be rendered.
        "
        <p id="<get-var anchor />"><b><get-var question-number />. <get-var title /></b></p>
        %body
        "
;;; If not
    "<a href="answers.html#<get-var anchor />"><get-var question-number />. <get-var title /></a><br />"
    />
;;; Restore their previous values
<restore title />
<restore anchor />
</define-tag>