load_files.R

library("dplyr")
library("readr")
library("stringi")

# load file with names absolute paths
file.list <- list.files("/Volumes/gaia/", pattern='*.txt', full.names = TRUE)
# read them all as a list
df.list <- lapply(file.list, read_tsv)
# name list with correct id extracted from filenames
names(df.list) <- stri_extract_first(basename(file.list), regex = "patient_\\d")
# rbind as single data.frame, id column is filled with extracted info in filenames
df <- bind_rows(df.list, .id = "id")

# as function
load_data <- function(abspath, ext, pattern){
  file.list <- list.files(abspath,
                          pattern = ext, full.names = TRUE) # load file names absolute paths
  df.list <- lapply(file.list, read_tsv) # read them all as a list
  names(df.list) <- stri_extract_first(basename(file.list), regex = pattern) # name list with correct id 
  bind_rows(df.list, .id = "id") 
}