<?xml version="1.0" encoding="UTF-8"?>
<flow>
    <chain name="chain1">
        <then value="a,b,c"/>
    </chain>

    <chain name="chain2">
    </chain>
    <chain name="chain3">
        <then value="a" />
        <when value="b,c" errorResume="false" />
    </chain>

    <chain name="chain4">
        <then value="c,d"/>
    </chain>
</flow>