Couldn't match expected type ‘Text’ with actual type ‘Data.MonoTraversable.Element mono0’ The type variable ‘mono0’ is ambiguous

Question

I'm trying to create html nodes but running into this error:

Web/View/HardwareVendors/Show.hs:7:33
    • Couldn't match expected type ‘Text’
                  with actual type ‘Data.MonoTraversable.Element mono0’
      The type variable ‘mono0’ is ambiguous
    • In the second argument of ‘forEach’, namely ‘renderInput’
      In the first argument of ‘toHtml’, namely
        ‘((forEach hardwareVendor.required_fields) renderInput)’
      In the expression:
        toHtml ((forEach hardwareVendor.required_fields) renderInput)
  |
7 |     html ShowView { .. } = [hsx|
  |                                 ^...

related source code:

module Web.View.HardwareVendors.Show where
import Web.View.Prelude

data ShowView = ShowView { hardwareVendor :: HardwareVendor }

instance View ShowView where
    html ShowView { .. } = [hsx|
        {breadcrumb}
        <h1>{hardwareVendor.name}</h1>
        <form action="{hardwareVendor.getUrl}" method="get">
            -- required_fields is a Text[] postgres column
            {forEach hardwareVendor.required_fields renderInput}
            <input type="submit" value="Submit">
        </form>
    |]
        where
            breadcrumb = renderBreadcrumb
                            [ breadcrumbLink "HardwareVendors" HardwareVendorsAction
                            , breadcrumbText "Show HardwareVendor"
                            ]
renderInput :: Text -> Html
renderInput field = [hsx|
    <label for="{field}">{field}</label>
    <input type="text" id="{field}" name="{field}" required>
    <br>
|]

here's some extra filler words because stack overflow validation is silly. here's some extra filler words because stack overflow validation is silly.

Answer 1

Assuming that this is a normal IHP database record, the hardwareVendor.required_fields should be hardwareVendor.requiredFields as IHP fields are always camel case