From: Jeremy McAnally <jeremymcanally@...>
Date: 2007-10-15T12:31:26+09:00
Subject: Re: nil.to_i returning zero

I expect to get a converted object or some *Error (TypeError maybe?)
back from any to_* method.  Giving me the same object back or nil
doesn't make any sense...

As others have noted, I think the current behavior makes sense: I have
nil (whatever...money, cats, etc.) I'd think an integer representation
would be 0.

--Jeremy

On 10/14/07, Gerardo Santana Gómez Garrido <gerardo.santana@gmail.com> wrote:
> zero in Ruby is true, not false, in a boolean context.
>
> What does false.to_i return? An exception. There is not a numeric
> interpretation for false.
>
> What about nil. nil is nothing. The only other object that evaluates
> to false in a boolean context.
>
> What does nil.to_i return? Zero. And I wonder why. How can nil be
> interpreted as a number. It's beyond me.
>
> Anyone care to explain it to me?
>
> So far I've found the following links about the issue:
>
> http://www.oreillynet.com/ruby/blog/2005/12/is_this_a_good_thing_or_not.html
> http://journal.dedasys.com/articles/2007/05/08/rails-bitten-by-rubys-nil-to_f
> http://groups.google.com/group/ruby-talk-google/browse_thread/thread/a475bb8a541f700e/b9f0cac6945a4210?lnk=gst&q=nil.to_i#b9f0cac6945a4210
>
> --
> Gerardo Santana
>
>


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