Run time error, rule 'has_no_curried_macro_CasePatterns;402' in module 'transform' does not match

The compiler crashes on the program below due to an unimplemented pattern in has_no_curried_macro_CasePatterns. This happens for both empty and empty2.

import StdOverloadedList

Start = empty (L [|1])

:: L a = L ![a!]

empty l :== case l of
	L [|] -> True
	_     -> False

empty2 l :== l=:(L [|])