From: Todd Benson <caduceass@...>
Date: 2008-02-16T22:36:59+09:00
Subject: Re: Alter String base class to perform new (private methods) before returning itself when called by print statements

On Feb 16, 2008 12:29 AM, Steven G. Harms <steven.harms@gmail.com> wrote:
> class String
>   def summon
>     puts "You summon: " + self
>   end
>   def summon2
>     puts "You summon: " + self.gsub('x','y')
>   end

Keep in mind that these methods output what you want in irb, but
return nil.  In my irb session it looks something like this...
irb(main):001:0> class String
irb(main):002:1>   def summon
irb(main):003:2>     puts "You summon: " + self
irb(main):004:2>   end
irb(main):005:1> end
=> nil
irb(main):006:0> s = "hello".summon
You summon: hello
=> nil
irb(main):007:0> s
=> nil

>   def to_s
>     return "Atreyu"
>   end
> end
>
> "Artax".summon
> "Artax".summon2
>
> puts "Artax".to_s # reference 1
> puts "Artax"        # reference 2
>
> This produces...
>
> You summon: Artax
> You summon: Artay
> Atreyu
> Artax
>
> Now the "summon" methods indicate to me that by referencing self in
> methods added to the String class, you can alter the string from
> within itself.

Yes, this is possible.

> The question is, how can I get `puts "Artax" ` to
> produce the same results as `puts "Artax"`.  They are both Strings
> and, as far as I understand it, to_s is what is used to get a String's
> display value.
>
> Question #1:  Is there a way to references 1 and 2, supra, to do the
> same thing?

Look at these two (using the previous code)...

puts s.to_s
puts(s).to_s

>
> Thanks,
>
> Steven

Todd