R: Parse 'args' based on command-line interface described in...

docopt {docopt} | R Documentation

## Parse `args` based on command-line interface described in `doc`.

### Description

`docopt` creates your command-line interface based on its description that you pass as `doc`. Such description can contain –options, <positional-argument>, commands, which could be [optional], (required), (mutually | exclusive) or repeated...

### Usage

    docopt(doc, args = commandArgs(TRUE), name = NULL, help = TRUE,
      version = NULL, strict = FALSE, strip_names = !strict,
      quoted_args = !strict)

### Arguments

`doc` | `character` vector with command line specification
`args` | `character` vector of commandline arguments. If `args` is missing `commandArgs(trailingOnly=TRUE)` will be used.
`name` | Currently not used
`help` | `logical` should "-h" or "–help" generate a usage string?
`version` | `character`. If supplied the option "-v" generates the given version number and stops.
`strict` | `logical` if `TRUE` docopt will conform to docopt.py in and output (`strip_names=FALSE` and `quoted_args=FALSE`)
`strip_names` | if `TRUE` it will remove dashes and angles from the resulting names and add these to the resulting list. Note that this is different from docopt standard!
`quoted_args` | if `TRUE` it will accept quoted arguments. Note that this is different from docopt standard!

### Value

named list with all parsed options, arguments and commands.

### References

http://docopt.org,

### Examples

    "Usage: my_program.R [-hso FILE] [--quiet | --verbose] [INPUT ...]

    -h --help    show this
    -s --sorted  sorted output
    -o FILE      specify output file [default: ./test.txt]
    --quiet      print less text
    --verbose    print more text" -> doc
    docopt(doc, "-s --quiet")

[Package docopt version 0.6 Index]