From: Michael Fellinger <m.fellinger@...>
Date: 2007-07-26T11:00:27+09:00
Subject: Re: rtrim and ltrim function for ruby: is this ok?

On 7/26/07, Ian Whitlock <iw1junk@comcast.net> wrote:
> Leon Bogaert wrote:
> > This works. But I would rather see the first object changed. Is this
> > possible?
>
> I would argue that ltrim and rtrim should not remove one character, but
> a sequence of the given character.  The following code probably does
> not meet all ruby conventions, but it does what you request and it does
> reserve ! for its intended purpose.

Since we got the power of regex/gsub, let's use it :)

class String
  def rtrim(char)
    dump.rtrim!(char)
  end

  def rtrim!(char)
    gsub!(/#{Regexp.escape(char)}+$/, '')
  end

  def ltrim(char)
    dump.ltrim!(char)
  end

  def ltrim!(char)
    gsub!(/^#{Regexp.escape(char)}+/, '')
  end
end

s = "aaaaaabacbccccc"
p s
s.rtrim!("c")
p s
s.ltrim!("b")
p s
s.ltrim!("a")
p s