Re: Implicit Conversion Not Applied Automatically

On Sun, Aug 19, 2012 at 2:29 PM, Seyed H. HAERI (Hossein)
<hossein.haeri@...> wrote:
> Dear all,
>
> I have a class C for an instance c of which I would like the expression
>
> c < b
>
> to have a certain meaning. However, in my application, I would rather do so
> without touching C itself. To that end, I implemented a very simple wrapper
> around C which merely augments C with a < operator:
>
> case class CLessThanWaiter(c: C) {
>   def < (b: B) = ...
> }
>
> I also have an implicit conversion c2CLTW in my package object for getting C
> instances silently converted into CLessThanWaiter. Strangely enough, for a
> code fragment c < b, the compiler complains about C not having a member <,
> whilst things run perfectly when I change that into c2CLTW(c) < b. How come
> is that really possible? It looks to me like the compiler somehow fails to
> automatically understand that the implicit is applicable. Yet, it doesn't
> complain about its applicability when I use it manually. Is that a bug?
>
> I'm happy to provide my exact pieces of code if you think that helps in the
> diagnosis. Just didn't want to clutter the question with unrelated
> material...

You might like to troubleshoot it further with scalac -Yinfer-debug.

Otherwise, post a small code sample to demonstrate.

-jason