call CheckDefFailure(['let $VAR = 5'], 'E1016: Cannot declare an environment variable:')
call CheckScriptFailure(['vim9script', 'let $ENV = "xxx"'], 'E1016:')
- call CheckDefFailure(['let @~ = 5'], 'E1066:')
+ if has('dnd')
+ call CheckDefFailure(['let @~ = 5'], 'E1066:')
+ else
+ call CheckDefFailure(['let @~ = 5'], 'E354:')
+ call CheckDefFailure(['@~ = 5'], 'E354:')
+ endif
call CheckDefFailure(['let @a = 5'], 'E1066:')
call CheckDefFailure(['let @/ = "x"'], 'E1066:')
call CheckScriptFailure(['vim9script', 'let @a = "abc"'], 'E1066:')