From: Paul Lutus <nospam@...>
Date: 2006-12-05T03:15:09+09:00
Subject: Re: How to use a String obj both in Proc.new and for puts

Richard wrote:

> Hi All,
> 
> In the appended code I duplicate the text so I can both display it and
> define a new Proc.  Is there away I can use, say,
> 
> text = '[*1..n].join(", ")'
> 
> in the body of the Proc spec. and thus simply
> 
> puts text?

Are you asking how to create a string that can serve for display and also
serve as the executable content of a Proc instance?

--------------------------------------

#!/usr/bin/ruby -w

s = "x = Math.sqrt(2);puts x * x;"

p = Proc.new { eval s }

puts s

p.call()

--------------------------------------

Output:

x = Math.sqrt(2);puts x * x;
2.0

Or are you asking how to cause the proc object to be executed when you put
it in this kind of context:

puts proc_object

For the second case, you could create a class that redefines to_s:

class UntestedExample
  def to_s
    return p.call() # something like this
  end
end

ute = UntestedExample.new

puts ute

-- 
Paul Lutus
http://www.arachnoid.com