Error when trying to not use a help flag

[trevorld]

Mentioned here trevorld/r-getopt#9

Code like this should work:

option_list_neg <- list( make_option(c("-h", "--mean"), default=0.0) )
parser <- OptionParser(usage = "\\%prog [options] file", option_list=option_list_neg, add_help_option=FALSE)
args <- parse_args(parser, args = c("-h", "-5.0"))
expect_equal(args, list(mean = -5.0))