this is a typo
you can use get() to get the dataframe associated with a name (which you can make by pasting together parts of names). its the inverse of assign().
(ex1 <- data.frame(
joinbyme =c(1,2,3),
letters = letters[1:3]
))
(ex2 <- data.frame(
joinbyme =c(1,2,3),
LETTERS = LETTERS[1:3]
))
full_join(get(paste0("ex",1)),
get(paste0("ex",2)),
by="joinbyme"
)