Api-blueprint: Null default value for attribute

[AlexKorovyansky]

How to define string attribute with null as default value?

I'm trying:

+ Attributes
   + prev: null (string) - Prev page url 

But apiary interprets it as "null", that's not null.

[zdne]

Please see (and feel free to chime in) to the discussion here https://github.com/apiaryio/mson/issues/26

[HansHauge]

That other conversation thread is very long. At the end they decided to allow (string, nullable) if a string might be null for example.

Adding this because this issue is the first Google result, should save someone some time.