Right, Julia is dynamically but nonetheless very strongly typed. If you write `x::String` then x is a string; you won't ever get a surprise null pointer error f

Right, Julia is dynamically but nonetheless very strongly typed. If you write `x::String` then x is a string; you won't ever get a surprise null pointer error from that code, and `nothing` doesn't tend to propagate far from where it appeared (the core problem in languages like Java). In future we'll likely have shortcuts for `T?` as `Union{T,Nothing}`; effectively a dynamic version of optional/maybe types, as in Swift and others.