> Default Not Nil (and cleaning up the associated initialization that springs > from this). Newbies always get caught with a seq that hasn't been > initialised. If you want nil, be explicit about it.
The better solution for today's Nim is to remove `nil` from seqs. Internally `@[]` can be `nil`, but there is no reason to expose this implementation detail. `len` already returns 0 for nil seqs. The same is true for `string`.
