anchor.diff:      let customOperationMethods = 
           AllMethInfosOfTypeInScope cenv.infoReader env.NameEnv (None,ad) IgnoreOverrides mBuilderVal builderTy
           |> List.choose (fun methInfo -> 
  -                if IsMethInfoAccessible cenv.amap mBuilderVal ad methInfo then
  -                    let nameSearch = 
  -                        TryBindMethInfoAttribute cenv.g mBuilderVal cenv.g.attrib_CustomOperationAttribute methInfo 
  -                                     (fun _ -> None) // We do not respect this attribute for IL methods
  -                                     (function (Attrib(_,_,[ AttribStringArg msg ],_,_,_,_)) -> Some msg | _ -> None)
  -                                     (fun _ -> None) // We do not respect this attribute for provided methods
  -
  -                    let joinConditionWord =
  -                        TryBindMethInfoAttribute cenv.g mBuilderVal cenv.g.attrib_CustomOperationAttribute methInfo 
  -                                     (fun _ -> None) // We do not respect this attribute for IL methods
  -                                     (function (Attrib(_,_,_,ExtractAttribNamedArg "JoinConditionWord" (AttribStringArg s),_,_,_)) -> Some s | _ -> None)
  -                                     (fun _ -> None) // We do not respect this attribute for provided methods
  -                    let flagSearch (propName:string) = 
  -                        TryBindMethInfoAttribute cenv.g mBuilderVal cenv.g.attrib_CustomOperationAttribute methInfo 
  -                                     (fun _ -> None) // We do not respect this attribute for IL methods
  -                                     (function (Attrib(_,_,_,ExtractAttribNamedArg propName (AttribBoolArg b),_,_,_)) -> Some b | _ -> None)
  -                                     (fun _ -> None)// We do not respect this attribute for provided methods
  -                    let maintainsVarSpaceUsingBind = defaultArg (flagSearch "MaintainsVariableSpaceUsingBind") false
  -                    let maintainsVarSpace = defaultArg (flagSearch "MaintainsVariableSpace") false
  -                    let allowInto = defaultArg (flagSearch "AllowIntoPattern") false
  -                    let isLikeZip = defaultArg (flagSearch "IsLikeZip") false
  -                    let isLikeJoin = defaultArg (flagSearch "IsLikeJoin" ) false
  -                    let isLikeGroupJoin = defaultArg (flagSearch "IsLikeGroupJoin" ) false
  -
  -                    match nameSearch with  
  -                    | None -> None
  -                    | Some nm -> Some (nm, maintainsVarSpaceUsingBind, maintainsVarSpace, allowInto, isLikeZip, isLikeJoin, isLikeGroupJoin, joinConditionWord, methInfo)
  -                else
  -                    None)
  +                if not (IsMethInfoAccessible cenv.amap mBuilderVal ad methInfo) then None else
  +                let nameSearch = 
  +                    TryBindMethInfoAttribute cenv.g mBuilderVal cenv.g.attrib_CustomOperationAttribute methInfo 
  +                                 (fun _ -> None) // We do not respect this attribute for IL methods
  +                                 (function (Attrib(_,_,[ AttribStringArg msg ],_,_,_,_)) -> Some msg | _ -> None)
  +                                 (fun _ -> None) // We do not respect this attribute for provided methods
  +
  +                let joinConditionWord =
  +                    TryBindMethInfoAttribute cenv.g mBuilderVal cenv.g.attrib_CustomOperationAttribute methInfo 
  +                                 (fun _ -> None) // We do not respect this attribute for IL methods
  +                                 (function (Attrib(_,_,_,ExtractAttribNamedArg "JoinConditionWord" (AttribStringArg s),_,_,_)) -> Some s | _ -> None)
  +                                 (fun _ -> None) // We do not respect this attribute for provided methods
  +                let flagSearch (propName:string) = 
  +                    TryBindMethInfoAttribute cenv.g mBuilderVal cenv.g.attrib_CustomOperationAttribute methInfo 
  +                                 (fun _ -> None) // We do not respect this attribute for IL methods
  +                                 (function (Attrib(_,_,_,ExtractAttribNamedArg propName (AttribBoolArg b),_,_,_)) -> Some b | _ -> None)
  +                                 (fun _ -> None)// We do not respect this attribute for provided methods
  +                let maintainsVarSpaceUsingBind = defaultArg (flagSearch "MaintainsVariableSpaceUsingBind") false
  +                let maintainsVarSpace = defaultArg (flagSearch "MaintainsVariableSpace") false
  +                let allowInto = defaultArg (flagSearch "AllowIntoPattern") false
  +                let isLikeZip = defaultArg (flagSearch "IsLikeZip") false
  +                let isLikeJoin = defaultArg (flagSearch "IsLikeJoin" ) false
  +                let isLikeGroupJoin = defaultArg (flagSearch "IsLikeGroupJoin" ) false
  +
  +                match nameSearch with  
  +                | None -> None
  +                | Some nm -> Some (nm, maintainsVarSpaceUsingBind, maintainsVarSpace, allowInto, isLikeZip, isLikeJoin, isLikeGroupJoin, joinConditionWord, methInfo))
   
       let customOperationMethodsIndexedByKeyword = 
           customOperationMethods
  
positive.code:     let GenerateMatchingSimpleArgumentTypes (calledMeth:MethInfo) =
          let curriedMethodArgAttribs = calledMeth.GetParamAttribs(cenv.amap, mItem)
          curriedMethodArgAttribs
          |> List.map (fun args -> List.filter isSimpleFormalArg args |> NewInferenceTypes)
  
      let UnifyMatchingSimpleArgumentTypes exprTy (calledMeth:MethInfo) =
          let curriedArgTys = GenerateMatchingSimpleArgumentTypes calledMeth
  
negative.code:     let modrefs = ForceRaise (TcModuleOrNamespaceLidAndPermitAutoResolve env amap longId)
  
      // validate opened namespace names
      for id in longId do
          if id.idText <> MangledGlobalName then
              CheckNamespaceModuleOrTypeName g id
  
      let IsPartiallyQualifiedNamespace (modref: ModuleOrNamespaceRef) = 
          let (CompPath(_,p)) = modref.CompilationPath 
  