<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
    <defs>
        <pattern id="pattern1f" y="0" xlink:href="#pattern1e"/>
        <pattern id="pattern1e" x="0" xlink:href="#pattern1d"/>
        <pattern id="pattern1d" width="50" xlink:href="#pattern1c"/> 
        <pattern id="pattern1c" xlink:href="#pattern1b">
            <rect x="0" y="0" width="50" height="30" fill="blue" stroke="green"/>
        </pattern>
        <pattern id="pattern1b" height="30" xlink:href="#pattern1a"/>
        <pattern id="pattern1a" patternUnits="userSpaceOnUse"/>

        <pattern id="pattern1" xlink:href="#pattern1f"/>

        <pattern id="pattern2" patternUnits="userSpaceOnUse" x="0" y="0" width="50" height="30">
           <rect x="0" y="0" width="50" height="30" fill="blue" stroke="green"/>
        </pattern>
    </defs>

    <rect transform="translate(50,10)" fill="url(#pattern1)" width="100px" height="100px"/>
    <rect transform="translate(200,10)" fill="url(#pattern2)" width="100px" height="100px"/>
    <text x="10" y="150">The above two squares should be blue-red patterns and look identical</text>
</svg>