<function name="factorial" args="num">
    <if>
        <eq>
            0
            <var>num</var>
        </eq>
        <return>1</return>
        <else>
            <return>
                <mul>
                    <var>num</var>
                    <call name="factorial">
                        <sub>
                            <var>num</var>
                            1
                        </sub>
                    </call>
                </mul>
            </return>
        </else>
    </if>
</function>

<for var="i">
    <range from="1" to="100"/>
    <print end=" ">
        <call name="factorial">
            <var>i</var>
        </call>
    </print>
</for>