From: Robert Dober <robert.dober@...>
Date: 2006-11-21T20:24:45+09:00
Subject: Re: Bug in ruby?

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On 11/21/06, Justin Collins <collinsj@seattleu.edu> wrote:
>
> AliasX Neo wrote:
> > Well, I've spent the last hour or so debugging one of the stupidest
> > errors I have encountered with Ruby.
> >
> >
> <snip>
> > I debugged the application and put a mark on the first line to examine
> > it in the following code:
> >
> > [code]def parse(string, starting, ending)
> >         length = starting.length
> >         istart = string.index(starting) + length
> >         iend = string.index(ending, istart)
> >         return string.slice(istart, iend - istart)
> >     end[/code]
> >
> > And the debugger said that length was an int with the value of 15. Guess
> > what still happened? Got the exact same error with the + operator on a
> > nil object. Except that completely contradicts the fact that it's not
> > nil but it's an int with the value of 15.
> >
>
> + is being called on string.index(starting) not length. I'd check to
> make sure you aren't getting nil from that:


which is expected behavior
http://www.ruby-doc.org/core/classes/String.html#M000805
cheers
Robert

def parse(string, starting, ending)
>         p string.index(starting)
>         istart = string.index(starting) + length
>         iend = string.index(ending, istart)
>         return string.slice(istart, iend - istart)
> end
>
> Hope that helps.
>
> -Justin
>
>


-- 
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore all progress
depends on the unreasonable man.

- George Bernard Shaw

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