From: Justin Collins <justincollins@...>
Date: 2009-08-21T18:34:48+09:00
Subject: Re: [regexp] How to convert string "/regexp/i" to /regexp/i - ?

Joao Silva wrote:
> When i try to use:
>
>   
>>> Regexp.new("/regexp/i")
>>>       
> => /\/regexp\/i/
>
> But it's not what i want - i need:
>
> /regexp/i
>
> :-(
>
> How i can convert this proper way?
>   

If that is exactly the kind of string you are expecting, I think you are 
stuck with having to use eval.

irb(main):001:0> r = eval("/regexp/i")
=> /regexp/i
irb(main):002:0> r.match("REGEXP")
=> #<MatchData "REGEXP">

If you do not need the options, you could just grab the inner part and 
make a regexp out of that:

irb(main):001:0> re = "/som.r.g.x\d+/i"
=> "/som.r.g.xd+/i"
irb(main):002:0> re = "/som.r.g.x\\d+/i".match(/\/(.*)\/[^\/]/)[1]
=> "som.r.g.x\\d+"
irb(main):003:0> /#{re}/.match("someregex1123")
=> #<MatchData "someregex1123">

Not really a great solution, though, as you lose information.

-Justin