R equivalent of python module structure and functionality?
summary: how to structure an R file such that it can be both 1. used as a script via, e.g., (from OS commandline) $ Rscript foo.r bar=baz 2. imported and called as a function via, e.g. (from R commandline)
source('./foo.r)
foo(bar='baz')
? I'm looking for the 'R equivalent' of how python supports this usecase. details: As discussed in the thread beginning https://stat.ethz.ch/pipermail/r-help/2012-September/323255.html I have a script https://github.com/TomRoche/GEIA_to_netCDF/blob/master/netCDF.stats.to.stdout.r that takes named arguments without undue pain. I would also like to be able to call it as a function from other scripts. How to do that in R? In case that's not specific enough :-) I know how to structure files/ modules in python like http://python.net/~goodger/projects/pycon/2007/idiomatic/cmdline.py (i.e., generically, http://python.net/~goodger/projects/pycon/2007/idiomatic/handout.html#module-structure
"""module docstring"""
# imports
# constants
# exception classes
# interface functions
# classes
# internal functions & classes
def main(...):
...
if __name__ == '__main__':
status = main()
sys.exit(status)
) so that the file/module is both 1. callable from the OS commandline via, e.g., $ /path/to/cmdline.py 2. importable without mere import causing execution of the script's functionality, e.g.,
sys.path.append('/path/to')
from cmdline import *
process_command_line(...)
How to do this in R? TIA, Tom Roche <Tom_Roche at pobox.com>