Question: In play 2.1 reads are used to marshall Json to objects. But how can I do this when the case class has only one field. The ideom that works for more fields does not work, as with one field 'and' is not used. Thus I do not get a FunctionBuilder.

The following code gives me a type mismatch. How can I fix this?

```
case class Data(stamm: Seq[String])

implicit val dataReads  = (
  (__ \ "stamm").read(Reads.list[String])
)(Data)

```

Answer: 
Json combinators doesn't work for single field case class.

Pascal (writer of this API) has explained this situation here
<https://groups.google.com/forum/?fromgroups=#!starred/play-framework/hGrveOkbJ6U>

There are some workarounds which works, like this one:

```
case class A(value: List[Int])
val areads = (__ \ 'value).read[List[Int]].map{ l => A(l) } // covariant map

```
Even simpler solution than the accepted one:

```
case class A(value: String)
val reads = (__ \ "key").read[String].map(A.apply)

```