Command-line and scripting front-end for R
r binary provides a convenient and powerful front-end. By
embedding R, it permits four distinct ways to leverage the power of R at
the shell prompt: scripting, filename execution, piping and direct
r front-end was written with four distinct usage modes in mind.
First, it allow to write so-called ‘shebang’ scripts starting with
#!/usr/bin/env r. These ‘shebang’ scripts are perfectly suited for
automation and execution via e.g. via
Second, we can use
r somefile.R to quickly execute the name R source
file. This is useful as
r is both easy to type—and quicker to start
R itself, or its scripting tool
Rscript, while still
r can be used in ‘pipes’ which are very common in Unix. A
simple and trivial example is
echo 'cat(2+2)' | r illustrating that
the standard output of one program can be used as the standard input of
r can be used as a calculator by supplying expressions after
Common with other shell tools and programs,
r returns its exit code
where a value of zero indicates success.
On OS X one may have to link the binary to, say,
lr instead. As OS X
insists that files named
r are the same, we cannot use the
Jeff Horner and Dirk Eddelbuettel wrote
littler from 2006 to today,
with contributions from several others.
Dirk Eddelbuettel email@example.com is the maintainer.
## Not run: #!/usr/bin/env r ## for use in scripts other input | r ## for use in pipes r somefile.R ## for running files r -e 'expr' ## for evaluating expressions r --help ## to show a quick synopsis ## End(Not run)