Based how I think MappedLongForeignKey works, I would expect
Comment.parentComment to already have the parent instance, but I
haven't tested this.

Peter

On Nov 16, 8:57 am, Trevor Austin <[email protected]> wrote:
> I have an object type representing a threaded comment that I want to
> organize into trees - what's the best way to represent this
> relationship with Mapper?  My naive idea is to do something like:
>
> class Comment extends LongKeyedMapper[Comment] with IdPK {
>   ...
>   object parentComment extends MappedLongForeignKey(this, Comment) {
>     override def dbColumnName = "parent_comment_id"
>     override def defaultValue = -1
>   }
>   ...
>   def getParentComment():Box[Comment] = {
>     if(this.parentComment.is == -1) {
>       Empty
>     }
>     else {
>       Comment.find(By(Comment.id, this.parentComment))
>     }
>   }
>
> }
>
> Is there a way to do this more directly so that Comment.parentComment
> just gives me something I can feed into type matching rather tahn
> doing the explicit check against -1 in a wrapper funciton?
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