local a: number = "hello"
print(a)

I would sincerly hope that this raises something in Luau who has a type system as a selling point, yet going by the demo, this is perfectly valid code: https://luau.org/demo?share=H4sIAAAAAAAACsvJT07MUUi0UsgrzU1KLVKwVVDKSM3JyVfiKijKzCvRSNTkAgAit0M6IwAAAA%3D%3D