R: Read a text file, process the text with a function, and write...

process_file {xfun} | R Documentation

## Read a text file, process the text with a function, and write the text back

### Description

Read a text file with the UTF-8 encoding, apply a function to the text, and write back to the original file.

### Usage

    process_file(file, fun = identity, x = read_utf8(file))

    sort_file(..., fun = sort)

### Arguments

`file` | Path to a text file.
`fun` | A function to process the text.
`x` | The content of the file.
`...` | Arguments to be passed to `process_file()`.

### Details

`sort_file()` is an application of `process_file()`, with the processing function being `sort()`, i.e., it sorts the text lines in a file and write back the sorted text.

### Value

If `file` is provided, invisible `NULL` (the file is updated as a side effect), otherwise the processed content (as a character vector).

### Examples

    f = tempfile()
    xfun::write_utf8("Hello World", f)
    xfun::process_file(f, function(x) gsub("World", "woRld", x))
    xfun::read_utf8(f)  # see if it has been updated
    file.remove(f)

[Package xfun version 0.31 Index]