Why def is not a valid export prefix?

[soronpo]

Maybe in the future it will. See Martin’s comment here:

Proposed Changes and Restrictions For Implicit Conversions

It can be generally allowed for exports but not for imports. It’s a question of evaluation order. Say you have import f(x).a ... a + a when is f(x) evaluated? I believe it would have to be evaluated at the point where the import appears, so the code would rewrite to val $temp = f(x) ... $temp.a + $temp.a The alternative semantics would rewrite at the point of access, i.e.: ... f(x).a + f(x).a That would not only surprising and potentially costly. It would not work at all if we import a ty…