https://issues.dlang.org/show_bug.cgi?id=18545
--- Comment #1 from FeepingCreature <default_357-l...@yahoo.de> --- It turns out what's happening here is that cast() constNullable is equivalent to Nullable(constNullable)... which implicitly casts to constNullable.get. alias get this strikes again! Nullable should maybe have a copy constructor from const? --