AT
Apache TinkerPop•10mo ago
Lyndon

Casting issue with Gremlin Java

I wrote the following query and I can't get it to compile, tried a ton of casting but it just isn't happy... 
g.V(..).in(..).<some contraints that do not change it from a vertex).
        fold().project("visits", "form").
                    by(__.unfold().values("...").dedup().count()).
                    by(__.unfold().
                           repeat( __.in()).
                                    emit(__.<etc>))
                    
g.V(..).in(..).<some contraints that do not change it from a vertex).
        fold().project("visits", "form").
                    by(__.unfold().values("...").dedup().count()).
                    by(__.unfold().
                           repeat( __.in()).
                                    emit(__.<etc>))
The problem is because of the fold it loses the type and then the type going into the repeat will not allow me to execute an in() step. I tried casting the unfold() and the in() to GraphTraversal<Vertex, Vertex> and variations of that with 1 vertex switched for Object. I cannot get this to compile. Anyone have any ideas on how to cast this properly?
5 Replies
Lyndon
Lyndon•10mo ago
If I switch the by(__unfold() for by( V() it works but obviously that isn't what I want and i cant cast it to the type of V()...
redtree1112
redtree1112•10mo ago
I may be missing something but if you unfold() immediately after fold(), can you just omit it ? or does this work ? 
.by(__.<Vertex>unfold().repeat(__.in()))
.by(__.<Vertex>unfold().repeat(__.in()))
Lyndon
Lyndon•10mo ago
problem is when you go into the project without the fold it just gives 1 item in and so you have to fold before hand
redtree1112
redtree1112•10mo ago
Ah I see. Does specifying a type in generics above work ?
Lyndon
Lyndon•10mo ago
it did not, sorry I was moving and was away for a while I havent found a way to do it so I just rewrote the query to not require it
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