anchor.diff:                  yield! visitExpr e
               | SynExpr.Quote(_,isRaw,e,_,r) ->
                   // subtract columns so the @@> or @> is not collapsed
  -                let rEnd = mkPos r.End.Line (r.EndColumn-(if isRaw then 3 else 2)) 
  +                let rEnd = Range.mkPos r.End.Line (r.EndColumn-(if isRaw then 3 else 2)) 
                   yield mkFileIndexRange r.FileIndex r.Start rEnd
                   yield! visitExpr e
               | _ -> ()
  
positive.code:             | SynExpr.LetOrUse (_, _, bindings, body, _) ->
                  yield! visitBindings bindings
                  yield! visitExpr body
              | SynExpr.Match (seqPointAtBinding,_,clauses,_,r) ->
                  match seqPointAtBinding with
                  | SequencePointAtBinding pr ->
  
negative.code:     and private visitBinding (Binding(_,kind,_,_,_,_,_,_,_,e,range,_) as b) =
          seq {
              match kind with
              | SynBindingKind.NormalBinding ->
                  let r1 = b.RangeOfBindingSansRhs
                  let r2 = b.RangeOfBindingAndRhs
                  yield Range.endToEnd r1 r2
              | SynBindingKind.DoBinding ->
                  let doEnd = mkPos range.Start.Line (range.Start.Column + 2)
                  yield mkFileIndexRange range.FileIndex doEnd range.End
              | SynBindingKind.StandaloneExpression -> 
                  yield range
              yield! visitExpr e
          }
  
  