Unexpected compiler exception tupleHasFieldNames given non-Tuple type node

[jurgenvinju]

The following code triggers the exception mentioned in the subject of this issue:

module X

value x = ""()[\loc=|hello:///|];

It could produce a static error, because node do not have named fields per se, or even better it should simply set the \loc keyword field in the anonimous node and produce ""(\loc=|hello:///|) as a value assigned to x.