{"textDocument": {"uri": "file:///editCompletion.lean"},
 "position": {"line": 3, "character": 22}}
{"items":
 [{"label": "foo",
   "kind": 5,
   "data":
   {"params":
    {"textDocument": {"uri": "file:///editCompletion.lean"},
     "position": {"line": 3, "character": 22}},
    "id": {"const": {"declName": "Foo.foo"}},
    "cPos": 1}}],
 "isIncomplete": false}