Some way to find an element labelled by another

[avh4]

Split from #32 by request.

some way to find the input that's associated with a label that matched another selector. In this example, find the input associated with the "A" label, and not the other input (this should also work in cases where the input and the label aren't siblings):

div []
    [ label [ for "input-1" ] [ text "A" ]
    , label [ for "input-2" ] [ text "B" ]
    , input [ id "input-1" ] []
    , input [ id "input-2" ] []
    ]

Possible low-level API: (See also #51)

dom
    |> Query.find [ tag "label", text "A" ]
    |> Query.getAttribute "for"
    |> (\labelFor -> Query.find [ tag "input", id labelFor ] dom)

(I guess Query.getAttribute would probably have to return Result _ String or even Result _ (Maybe String) instead of String.)

Possible high-level API:

Query.find
    [ tag "input"
    , labelledBy [ tag "label", text "A" ]
    ]

Note that the solution should be usable both for the for attribute in label elements, and for aria-labelledby attribute on all elements.

[rtfeldman]

Related: #51