Could subplot have explicit error when ncols is passed?

I just tried to use subplot in a shiny app, and naively assumed that there would be an ncols argument corresponding to nrows - evidently, that is not really needed, but an error message clearer than Error in [[: subscript out of bounds would have saved me a lot of confusion. Might still be worth making this explicit? (Or - though that might be too much of a change - require all ... arguments to be unnamed?)

library(plotly)
p1 <- plot_ly(economics, x = ~date, y = ~uempmed)
p2 <- plot_ly(economics, x = ~date, y = ~unemploy)
subplot(p1, p2, ncols = 2)
#> Error in plots[[i]][["frames"]]: subscript out of bounds

^{Created on 2024-05-09 with reprex v2.0.2}

まず、提供された R の例を subplot のエントリーポイントで再現し、ncols 引数がどのように処理されるかを確認します。ncols を渡しても subscript-out-of-bounds エラーが発生せず、代わりに明確で意図されたメッセージが表示されれば完了です。結果を確認する際は、issue に記載されている既存の subplot の動作を考慮してください。