Is it correct for immutable struct fields to act like enum or static const fields? (I don't think so, but I am wrong often): struct Foo { immutable int x = 1; } static assert(Foo.sizeof == 4); void main() {} More info in the D.learn thread: http://www.digitalmars.com/webnews/newsgroups.php?art_group=digitalmars.D.learn&article_id=22540 Thank you, bearophile