Write a function to manipulate and then write a dataframe - r

Question

I would like to read in multiple .csv files (dataframes) from a folder and apply a function that I create to all the files. And finally this function will write the new .csv files.
I want the function to do the following 3 things
df$Class <- gsub("null", "OTHER", df$Class)
df$Class <- gsub(': ', ',', df$Class)
df <- df %>% select(c(Image, everything(.), -Name))
I don't really know how to put these thing into a function, but I've tried
`
file_names <- list.files(pattern = "\\.csv$")
tidy_up_fxn <- function(file_names) {
df <- do.call(bind_rows,lapply(file_names,data.table::fread))
df$Class <- gsub("null", "OTHER", df$Class)
df$Class <- gsub(': ', ',', df$Class)
df <- df %>% select(c(Image, everything(.), -Name))
out <- function(df)
fwrite(out, file = file_names, sep = ",")
}
tidy_up_fxn(file_names)
`
When I run it, R gets busy for a few seconds and then nothing happens. Please, help correct my function!

Answer 1

The following works the way I intended to
file_names <- list.files(pattern = "\\.csv$")
tidy_up_fxn <- function(file_names) {
df <- bind_rows(lapply(file_names,data.table::fread))
df$Class <- gsub("null", "OTHER", df$Class)
df$Class <- gsub(': ', ',', df$Class)
df <- df %>% select(c(Image, everything(.), -Name))
fwrite(df, file = "new.csv", sep = ",")
}
tidy_up_fxn(file_names)
Thank you all!!