From: Roel Harbers <rubycore@...>
Date: 2007-04-27T15:14:12+09:00
Subject: Re: [patch] gsub with backslash characters in replacement string

Adam Bozanich wrote:
> Thanks, now I understand the problem.
> 
> for the record, this still works after the patch:
> 
> "abc".gsub(/(.)/,'\1,') # => "a,b,c,"
> 
> It is difficult (impossible?), however, to produce a \1 in the output
> 
> irb(main):003:0> "abc".gsub(/(.)/,"\\\\1,")
> => "\\\\1,\\\\1,\\\\1,"
> 
> and similarly a '\' before a register replacement.
> 
> irb(main):016:0> "a".gsub(/(.)/,"\\\\\\1,")
> => "\\\\a,"
> 
> I guess I just like having the "regex identity" property :)
> 
> str = "\\" * 2
> str == str.gsub(str,str)  # => true
> 
> str = "a"
> str == str.gsub(str,str)  # => true
> 
> Sorry for the false bug.
> 
> -Adam

It may not be a bug, although it's definitly unexpected, but shouldn't
the documentation at least mention the double-escaping?

Regards,

Roel Harbers