Sourceval to_value :
t->[> `Structure of
(string
* [> `Structure of
(string
* [> `Enum of string| `List of
[> `String of string| `Structure of (string * [> `String of string ]) list ]
list| `Map of
([> `String of string ] * [> `String of string ]) list| `String of string ])
list ])
list ]