anchor.diff:  //     | query.Yield <expr>                            --> not IQueryable, seq { <expr> } 
   //     | query.YieldFrom <expr>                        --> not IQueryable, seq { yield! <expr> } 
   //     | query.Op(<qexprOuter>, <other-arguments>)     --> IQueryable if qexprOuter is IQueryable, otherwise query.Op(qexpOuter', <other-arguments>)   
  -
  -//printfn "found Query.Quote"
  -// If this returns "Some" then the source is not IQueryable.
   let rec tryRewriteToSeqCombinators g (e: Expr) = 
       let m = e.Range
       match e with 
  
positive.code:         else
              match x with
              | SizeValue (vdepth, vinfo) -> if vdepth < depth then x else MakeSizedValueInfo (bound depth vinfo)
              | ValValue (vr, vinfo)      -> ValValue (vr, bound (depth-1) vinfo)
              | TupleValue vinfos -> TupleValue (Array.map (bound (depth-1)) vinfos)
              | RecdValue (tcref, vinfos) -> RecdValue  (tcref, Array.map (bound (depth-1)) vinfos)
              | UnionCaseValue (ucr, vinfos) -> UnionCaseValue (ucr, Array.map (bound (depth-1)) vinfos)
              | ConstValue _             -> x
              | UnknownValue             -> x
              | CurriedLambdaValue(_lambdaId, _arities, _bsize, _expr', _ety) -> x
              | ConstExprValue (_size, _) -> x
      let maxDepth  = 6   (* beware huge constants! *)
      let trimDepth = 3
  
negative.code: 
  let [<Literal>] localVarSize = 1
  
  let AddTotalSizes l = l |> List.sumBy (fun x -> x.TotalSize) 
  
  let AddFunctionSizes l = l |> List.sumBy (fun x -> x.FunctionSize) 
  
  /// list/array combinators - zipping (_, _) return type
  let OrEffects l = List.exists (fun x -> x.HasEffect) l
  
  let OrTailcalls l = List.exists (fun x -> x.MightMakeCriticalTailcall) l
          
  let OptimizeList f l = l |> List.map f |> List.unzip 
  
  let NoExprs : (Expr list * list<Summary<ExprValueInfo>>) = [], []
  
  /// Common ways of building new value infos
  let CombineValueInfos einfos res = 
        { TotalSize  = AddTotalSizes einfos
          FunctionSize  = AddFunctionSizes einfos
  