var/let don't support multiple declarations yet

[survuvi]

let a : Int = 1

let b : Int = 2

# let a, b = 1, 2 # error declaration must have either a type or an initializer

# let a : Int, b : Int = 1, 2 error unknown tokens at the end of a declaration

print("a = ", a, " b = ", b)

[lattner]

+1, this isn't supported yet, but we definitely need to!