title: How do I modify a yaml field in go when I don't know every possible field in the yaml?
body: <p>How can I modify a field in yaml when I don't know every possible field the yaml can have? I can't define a struct that has every possible field, and <code>gopkg.in/yaml.v2</code> <code>Unmarshall</code> ignores fields that are not in the supplied struct, so <code>Marshall</code> loses any fields not in the struct, which is unacceptable.</p>
  
  <p>Is there a package that will allow me to dynamically specify a field name that will either return a basic value or struct if the field exists and nil/err otherwise? And marshall my changes out while preserving  all other fields from the input yaml?</p>
  
  <p>Thanks, Paul</p>