Exception with no useful information when using types with curly braces

[alvaroc1]

structural type Row c = Row

check : Row {Boolean} -> ()
check row = ()

value : Row {Text, Boolean}
value = Row

> check value

.alvaro.public> 
Encountered exception:
unpossible
CallStack ( from HasCallStack ) :
   error

i have no idea if the code should type-check or not, but the error should provide more details

[pchiusano]

Thanks for reporting. @dolio can you have a look when you’ve got a chance?