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}

Commencez par reproduire l’exemple R fourni au point d’entrée de subplot et examinez la façon dont l’argument ncols est géré. Le travail est terminé lorsque le passage de ncols ne produit plus l’erreur subscript-out-of-bounds, mais renvoie à la place un message clair et intentionnel ; tenez compte du comportement existant de subplot décrit dans l’issue lors de la vérification du résultat.