Thank you for your help and recommendations.
I still wondering, how to decide when is enough to use only the dots and when the quotation is required. In case of first example both solution are working.
fraction1 <- function(df, group, ...){
group = enquo(group)
df %>%
filter(...) %>%
vs
fraction1 <- function(df, group, ...){
group = enquo(group)
condition <- enquos(...)
df %>%
filter(!!!condition) %>%
But if I interpret correctly Hadley’s answer, even in the first case the tidyeval is working behind the scenes.