将命名元素追加到列表中

```{r}
res <- list()
res[["francais"]] <- list(elt1 = "salut", elt2 = "bonjour", elt3 = "au revoir")

toadd <- list(elt1 = "hello", elt2 = "good morning", elt3 = "bye")
```

I want to add `toadd` list with name "english" to list `res` :

2 solutions (`c` & `append`):

```{r}
res2 <- c(res, english = list(toadd))
res3 <- append(res, list(english = toadd))

identical(res2, res3) # TRUE
```