D-Programming-Language/phobos — pull request #2593 by MetaLang (2014-10-08 01:32:33+00:00)
Title: Fix Issue 9636: null initialization for std.typecons.Nullable

https://issues.dlang.org/show_bug.cgi?id=9636

For now, it's only allowed to use DefaultNullable on initialization. Nullable already has a Nullify function, so it's not as useful to also enable assigning DefaultNullable to a Nullable to nullify it.