# How to pass values down the pipe sequence?
**URL:** https://discourse.elm-lang.org/t/how-to-pass-values-down-the-pipe-sequence/4619
**Category:** Learn
**Created:** [November 6, 2019, 5:29pm UTC](https://discourse.elm-lang.org/t/how-to-pass-values-down-the-pipe-sequence/4619 "2019-11-06T17:29:54Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@kgashok](https://discourse.elm-lang.org/u/kgashok)
#### Post date: [November 6, 2019, 5:29pm UTC](https://discourse.elm-lang.org/t/how-to-pass-values-down-the-pipe-sequence/4619/1 "2019-11-06T17:29:54Z")
```auto
renderList2 : List Int -> Int -> Html msg
renderList2 lst limit =
let
attrBool x = if x > limit then True else False
in
lst
|> List.map (\i -> (String.fromInt i ++ ", "))
|> List.map (span [classList [("numberRed", True)] ] << List.singleton << text)
|> ul []
```
How do I pass the value of `i` to `attrBool x` so that the `attrBool` is `True` only when `i` \> `limit`?
---
### Author:  [@jfmengels](https://discourse.elm-lang.org/u/jfmengels)
#### Post date: [November 6, 2019, 5:43pm UTC](https://discourse.elm-lang.org/t/how-to-pass-values-down-the-pipe-sequence/4619/2 "2019-11-06T17:43:32Z")
In this case, you can do a single `List.map` for the transformation to a string and the transformation to a `span`. If you do these two operations in the same function, then you keep access to `i`.
Here is what I mean in code:
```elm
renderList2 : List Int -> Int -> Html msg
renderList2 lst limit =
let
attrBool x = if x > limit then True else False
in
lst
|> List.map (\i -> span [classList [("numberRed", attrBool i)] ] [text (String.fromInt i ++ ", ")])
|> ul []
```
---
### Author:  [@Atlewee](https://discourse.elm-lang.org/u/Atlewee)
#### Post date: [November 6, 2019, 11:10pm UTC](https://discourse.elm-lang.org/t/how-to-pass-values-down-the-pipe-sequence/4619/3 "2019-11-06T23:10:16Z")
You may know, but a tip if that is not the case… the if statement can also be done inline:
```auto
renderList2 : List Int -> Int -> Html msg
renderList2 lst limit =
lst
|> List.map (\i -> span [classList [("numberRed", i > limit )] ] [text (String.fromInt i ++ ", ")])
|> ul []
```
---
### Author:  [@kgashok](https://discourse.elm-lang.org/u/kgashok)
#### Post date: [November 7, 2019, 1:42pm UTC](https://discourse.elm-lang.org/t/how-to-pass-values-down-the-pipe-sequence/4619/4 "2019-11-07T13:42:58Z")
Yes, thanks for that tip. I used it.
---
### Author:  [@kgashok](https://discourse.elm-lang.org/u/kgashok)
#### Post date: [November 7, 2019, 1:44pm UTC](https://discourse.elm-lang.org/t/how-to-pass-values-down-the-pipe-sequence/4619/5 "2019-11-07T13:44:40Z")
But what if I want the value **`i`** to propagate down the pipeline, is it even possible?
---
### Author:  [@jfmengels](https://discourse.elm-lang.org/u/jfmengels)
#### Post date: [November 7, 2019, 2:15pm UTC](https://discourse.elm-lang.org/t/how-to-pass-values-down-the-pipe-sequence/4619/6 "2019-11-07T14:15:39Z")
It is possible, but you would have to be explicit about it. Basically, at every step of the pipeline, you’d return something (like a tuple), that contains `i` and the value you actually want to work on. Here is an example using a tuple:
```elm
renderList2 : List Int -> Int -> Html msg
renderList2 lst limit =
let
attrBool x = if x > limit then True else False
in
lst
|> List.map (\i -> (i, String.fromInt i ++ ", ")) -- Return a tuple
|> List.map (\(i, intAsText) -> -- Deconstructing the tuple
span [classList [("numberRed", attrBool i)] ] [text intAsText]
)
|> ul []
```
---
### Author:  [@system](https://discourse.elm-lang.org/u/system)
#### Post date: [November 17, 2019, 2:29pm UTC](https://discourse.elm-lang.org/t/how-to-pass-values-down-the-pipe-sequence/4619/7 "2019-11-17T14:29:41Z")
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