From: "David A. Black" <dblack@...>
Date: 2009-07-14T21:54:06+09:00
Subject: Re: a regex that does not contain comma

Hi --

On Tue, 14 Jul 2009, Glenn Jackman wrote:

>    case string
>    when /,/       then puts "#{string.inspect} contains a comma"
>    when /^[^,]*$/ then puts "#{string.inspect} has no comma"
>    end

That second regex, on its own, won't tell you the whole story:

   string = <<-EOM
   Hi.
   I have, at a minimum, two commas.
   Bye.
   EOM

   p "Match!" if /^[^,]*$/.match(string)
     => Match!

You'd want to use \A and \z, rather than ^ and $ (which delimit lines,
rather than the whole string).

But if you've already tested for /,/, then you should be able just to
have an else clause in your case statement, to cover cases where /,/
didn't match.


David

-- 
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