Catmandu::Fix::add_field

Contrary to "set_field", this will create the intermediate structures if they are missing.

   # Add a new field 'foo' with value 2
   add_field(foo, 2)
   # Change the value of 'foo' to 'bar 123'
   add_field(foo, 'bar 123')
   # Create a deeply nested key
   add_field(my.deep.nested.key, hi)

Catmandu::Fix