library(xtable)
texprint<-new.env(parent=.GlobalEnv)


texprint$print<-function(x, ...){
  UseMethod("texprint")
}
texprint$texprint.default <- function(x, ...){
  UseMethod("print")
}
texprint$texprint.data.frame <- function(x, ...){
  args<-list(...)
  xtable.arg.names <- intersect(names(args),setdiff(names(formals(xtable)),'...'))
  xtable.args <- args[xtable.arg.names]
  print.arg.names <- setdiff(names(args), xtable.arg.names)
  xt <- do.call(xtable, append(list(x=x), xtable.args))
  print.args <- args[print.arg.names]
  do.call(xtable:::print.xtable, append(list(x=xt), print.args))
}

data(cars)
mtcars
with(texprint, print(mtcars))
with(texprint, print(mtcars, caption='mtcars dataset from base R.'))