column name with brackets or other punctuations for dplyr group_by

Question

I have an imported data frame that has column names with various punctuations including parentheses, e.g. BILLNG.STATUS.(COMPLETED./.INCOMPLTE) .

I was

Answer 1

I'm just using this not-an-answer as a counter-example or illustration of limitations for the the backtick method. (It was the first strategem I tried. Perhaps it is the fact that two language operations ("(" and "/") are being handled adjacently that makes this fail.)

names(iris)[5] <- "Specie(/)s"
library(dplyr)
by_species <- iris %>% group_by(`Specie(/)s`)
by_species %>% summarise_each(funs(mean(., na.rm = TRUE)))
#Error: cannot modify grouping variable

Tried a variety or other language-oriented efforts with quote, as.name and substitute that also failed. (I wish there were a mechanism to request that this sink to the bottom of the answers.)