From: Logan Capaldo <logancapaldo@...>
Date: 2006-04-10T04:41:44+09:00
Subject: Re: Dumb reflection problem - create object from String


On Apr 9, 2006, at 3:21 PM, Robert Dober wrote:

> On 4/9/06, Brian Parkinson <parkI@whatevernot.com> wrote:
>>
>> Sven Klemm wrote:
>>
>> [deletia]
>>
>>> Module.const_get(s).new
>>
>> Thanks!
>>
>> I knew it would be a one-liner. :-)
>>
>> parki...
>
>
> I am afraid that the only  one-liner is eval :(
>
> suppose s contains the name of your class
> Module.const_get s does not work unless your class is defined on  
> top level.
> In oder to have the *same* semantics as
>
>    eval(s).new
>
> we have to write
>
> m = Module
> s.split(%r{::|\.}).each do
>     |name|
>     m = m.const_get(name)
> end
> m.new
>
> I suggest to look at ObjectSpace for another alternative, hardly more
> efficent though :(
>
> Robert
>
>
> --
> Deux choses sont infinies : l'univers et la b�tise humaine ; en ce qui
> concerne l'univers, je n'en ai pas acquis la certitude absolue.
>
> - Albert Einstein

s.split(/::/).inject(Object) { |p, c| p.const_get(c) }.new

There, a one liner (w/o any semi-colons)