HTMLBuilder func parameter for specific tag

[bgisme]

I'm trying to create something called Grid which initializes with only one or more Row.

So far this is what I came up with...

struct Grid<RowContent: HTML>: HTML {
    let rows: [Row<RowContent>]
    
    var content: some HTML {
        div {
            for row in rows {
                row
            }
        }
    }
    
    init(rows: () -> [Row<RowContent>]) {
        self.rows = rows()
    }
}

struct Row<InnerHTML: HTML>: HTML {
    let innerHTML: InnerHTML
    
    var content: some HTML {
        div {
            innerHTML
        }
    }
    
    init(@HTMLBuilder content: () -> InnerHTML) {
        self.innerHTML = content()
    }
}

But when I go to use Grid I have to put the Rows into an array like so...

struct MyBody<InnerHTML: HTML>: HTML {
    public var content: some HTML {
        Grid {
            [
                Row {
                    p{ "Row 0" }
                },
                Row {
                    p{ "Row 1" }
                },
            ]
        }
    }
}

I'd prefer to compose the Rows like any other HTML.

But if I use

@HTMLBuilder rows: () -> HTML

... it will allow any HTML and not just Rows.

Is there a way to write an HTMLBuilder func parameter like this?

init(@HTMLBuilder rows: () -> RowsHTML) { ... }

And then I can write Grid more naturally without arrays like below and only Rows are allowed...

Grid {
     Row {
          p{  "Row 0" }
     }
     Row {
          p{  "Row 1" }
     }
}

First I tried creating a new protocol on top of HTML called RowsHTML.

And then used that to restrict what is supplied to Grid.

public protocol RowsHTML: HTML { }

public struct Grid<Rows: RowsHTML>: HTML {
    let rows: Rows
    
    public var content: some HTML {
        div {
            rows
        }
    }
    
    public init(@HTMLBuilder rows: () -> Rows) {
        self.rows = rows()
    }
}

public struct Row<Inner: HTML>: RowsHTML {
    let innerHTML: Inner
    
    public var content: some HTML {
        div {
            innerHTML
        }
    }
    
    public init(@HTMLBuilder content: () -> Inner) {
        self.innerHTML = content()
    }
}

But when I use it in the code below, I get a compiler error:

Generic struct 'Grid' requires that '_HTMLTuple2<Row<p<HTMLText>>, Row<p<HTMLText>>>' (aka '_HTMLTuple2<Row<HTMLElement<HTMLTag.p, HTMLText>>, Row<HTMLElement<HTMLTag.p, HTMLText>>>') conform to 'RowsHTML'

Which I think means that it wants everything inside Row to be RowsHTML as well. And that seems excessive, having to add that protocol to every html element.

struct MyBody: HTML {
    public var content: some HTML {
        Grid {
            Row {
                p{ "Row 0" }
            }
            Row {
                p{ "Row 1" }
            }
        }
    }
}

Is there another way to approach this?