This is a command-line argument parser which wraps the powerful Perl module Getopt::Long and with some adaptations for easier use in R. It also provides a simple way for variable interpolation in R.
There are two vignettes in the package which explain in more detail:
Install
The package can be installed from CRAN:
install.packages("GetoptLong")or directly from GitHub:
devtools::install_github("jokergoo/GetoptLong")Usage
Control command line options
This package wraps the powerful Perl module Getopt::Long and keeps almost all features of it. The syntax of option specification is the same as Getopt::Long. So if you are from Perl and you know Getopt::Long, there would be no difficulty with using it.
The usage is very simple:
library(GetoptLong)
cutoff = 0.05
GetoptLong(
"number=i", "Number of items.",
"cutoff=f", "Cutoff for filtering results.",
"verbose!", "Print message."
)Then you can run this script by:
~\> Rscript foo.R --number 4 --cutoff 0.01 --verbose
~\> Rscript foo.R --number=4 --cutoff=0.01 --no-verbose
~\> Rscript foo.R -n 4 -c 0.01 -v
~\> Rscript foo.R -n 4 --verboseHelp message is automatically generated:
Usage: Rscript foo.R [options]
Options:
--number, -n integer
Number of items.
--cutoff, -c numeric
Cutoff for filtering results.
[default: 0.05]
--verbose
Print message.
--help, -h
Print help message and exit.
--version
Print version information and exit.
Variable interpolation
This package also supports simple variable interpolation, which means you can embed variables into texts directly, just like in Perl.
r = c(1, 2)
value = 4
name = "name"
qq("region = (@{r[1]}, @{r[2]}), value = @{value}, name = '@{name}'")
## [1] "region = (1, 2), value = 4, name = 'name'"So it would be much easier for you to construct complicated texts instead of using paste().
