> y <- iris[1:3,]
> x <- y
> x$Sepal.Width <- as.character(x$Sepal.Width)
> x$Sepal.Length <- as.factor(x$Sepal.Length)
> class(x[, 1])
[1] "factor"
> class(x[, 2])
[1] "character"
> class(x[, 3])
[1] "numeric"
> render_diff(diff_data(y, x))