From: Neville Burnell <Neville.Burnell@...>
Date: 2005-04-22T15:46:49+09:00
Subject: Re: Clean way to dynamically expand string with "#{expression}"?

How about:

irb(main):001:0> n = 1
=> 1
irb(main):002:0> s = 'n = #{n}'
=> "n = \#{n}"
irb(main):003:0> puts eval('"' + s + '"')
n = 1
=> nil 

-----Original Message-----
From: Taisuke Yamada [mailto:tyamadajp@list.rakugaki.org] 
Sent: Friday, 22 April 2005 4:35 PM
To: ruby-talk ML
Subject: Clean way to dynamically expand string with "#{expression}"?

Hi.

I'm trying to find a clean way to expand string with "#{...}".
What I want to do is essentially as follows:

  data = 123
  expr = 'data = #{data}'

  puts dosomething(expr)

and get 'data = 123' as a result. Actual content of 'expr' can be
anything, as long as it is a String object.

I came up with following:

  puts eval(%Q{"#{expr.gsub('"', '\"')}"})

But this is ugly, and I'm wondering if there's some other, cleaner way
to do the same thing.

Can anyone enlighten me?

Best Regards,
--
Taisuke Yamada