Issue #7537 has been updated by prijutme4ty (Ilya Vorontsov).


Sent a pull-request. https://github.com/ruby/ruby/pull/259
I've made changes the same way as python do -- http://docs.python.org/dev/library/argparse.html#arguments-containing 
This patch introduces one possible (but not very serious and very rare) incompatibility: if one already uses explicitly defined negative-digit option such as '-1' and also uses an option with optional argument '-p [ARG]' and runs a command with options '-p -1' then before patch it'll be treated as two different options '-p', '-1' and after patch they are treated as an option '-p' with value '-1'.
If one meets this problem, he can use option declaration with equal sign: '-p=[ARG]' or just change places of arguments and run his program with options '-1 -p'.
But I suppose not too many people use explicitly defined numeric options and even less people use optional argument with them in such order (may be even nobody use it such a way).
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Bug #7537: OptionParser treats negative digits as options
https://bugs.ruby-lang.org/issues/7537#change-37695

Author: prijutme4ty (Ilya Vorontsov)
Status: Assigned
Priority: Normal
Assignee: nobu (Nobuyoshi Nakada)
Category: lib
Target version: 
ruby -v: 1.9.3(p0, p327 both)


Is it intentional that negative digits are treated as options?
If I use negative digit as an argument of an option, it is treated as a number

OptionParser.new {|opts|
  opts.on('-p','--pvalue VAL', Integer, 'P-value') {|v|  puts "P-value: #{v}" }
}.parse!

`ruby my_test.rb -p -1` works normally

But if I use it as optional argument of an option:

OptionParser.new {|opts|
  opts.on('-p','--pvalue [VAL]', Integer, 'P-value') {|v|  puts "P-value: #{v}" }
}.parse!

`ruby my_test.rb -p -1` fails with "Invalid option -1"

Also I can't use it as non-optional argument

OptionParser.new {|opts|
  opts.on('-n', 'no Pvalue argument, other arguments only') {}
}.parse!
puts ARGV

`ruby my_test.rb -1` also fails with "Invalid option -1"


-- 
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