Combine all files in a directory into a single file

Lists the files in input_dir that match pattern, reads each one and writes their contents, in alphabetical order, to output_file. Each file's contents are preceded by a # FILE: <path> header block so the origin of every section is visible. If output_file lies inside input_dir, it is excluded so the file does not include itself. If no file matches, an empty output_file is written.

Usage

combine_files(
  input_dir = "working_functions",
  output_file = "all_functions.R",
  pattern = "\\.[Rr]$",
  recursive = TRUE
)

Arguments

input_dir

Character string. Directory to read files from. Default "working_functions".

output_file

Character string. Path of the combined file to write. An existing file is overwritten. Default "all_functions.R".

pattern

Regular expression that selects the files, passed to base::list.files(). Default "\\.[Rr]$" selects R scripts. Use NULL to include every file.

recursive

Logical. If TRUE (default), files in subdirectories of input_dir are included; if FALSE, only files directly in input_dir.

Value

Invisibly returns a character vector with the paths of the combined files. Called for its side effect of writing output_file.

Examples

# input_dir <- file.path(tempdir(), "combine_files_example")
# dir.create(file.path(input_dir, "sub"), recursive = TRUE, showWarnings = FALSE)
# writeLines("a <- 1", file.path(input_dir, "a.R"))
# writeLines("b <- 2", file.path(input_dir, "sub", "b.R"))
# output_file <- file.path(tempdir(), "combined.R")
# combine_files(input_dir = input_dir, output_file = output_file)
# cat(readLines(output_file), sep = "\n")
# combine_files(input_dir = input_dir, output_file = output_file, recursive = FALSE)