From: Peter Cooper <peter@...>
Date: 2007-06-25T08:56:51+09:00
Subject: Re: variables to call methods in ruby...

On 6/25/07, yermej@gmail.com <yermej@gmail.com> wrote:
> On Jun 24, 5:48 pm, Tim Hunter <TimHun...@nc.rr.com> wrote:
> > Harnish wrote:
> > > Essentially I want to call Test.func; but "func" lies in the variable
> > > testfunc; is it possible for me to invoke Test.func using variable
> > > testfunc?  If yes, how?  Any ideas, greatly appreciated.
> >
> > Check out the "__send__" method:
> >
> > var = "func"
> > obj.__send__(var, args)
>
> I've always used it without the underscores:

You can, but in case you're wondering the whys and wherefores of all
this.. it's possible to easily change the "send" method on a class
with anyone noticing.. this could cause "Bad Things"(tm) to happen.

It's possible to redefine __send__ too, but a warning is given and
it's generally considered bad form to redefine, delete, or otherwise
modify methods using the __x__ naming convention. You'll notice
classes like BlankSlate (
http://onestepback.org/index.cgi/Tech/Ruby/BlankSlate.rdoc ) take this
into account:

class BlankSlate
  instance_methods.each { |m| undef_method m unless m =~ /^__/ }
end

Cheers,
Peter Cooper
http://www.rubyinside.com/