read multiple csv or txt files, adding filename as a column, using data.table vs tidyverse

read_multiple_files.R

dirname = 'path/to/files'
files = list.files(dirname, pattern = "*_data.txt")

# tidyverse approach
library(tidyverse)
data = tibble(filename=files) %>%
  mutate(file_contents=map(filename, ~ read_tsv(file.path(dirname, .)))) %>%
  unnest()

# data.table approach
library(data.table)
data <- rbindlist(lapply(files, function(x) {
  dt = fread(file.path(dirname, x))
  dt$filename = x
  dt}))

# above, but functionalized
fread_directory <- function(dirname, pattern='*', label='filename') {
  files = list.files(dirname, pattern)
  scrub = sub('*','', pattern, fixed=TRUE)
  rbindlist(lapply(files, function(x) {
    dt = fread(file.path(dirname, x))
    dt[, label] = sub(scrub, '', x)
    dt
  }))
}