From: Jacob Fugal <lukfugl@...>
Date: 2006-04-12T02:30:23+09:00
Subject: Re: Oddities of Iteration

On 4/11/06, Nathan Olberding <nathan.olberding@gmail.com> wrote:
> puts "<div style=\"float:left;margin-right:2em\">Reports:"
> puts "<ol>"
> reports.each do |x|
>         begin
>                 puts "<li>" + x.to_s + "</li>"
>         rescue
>                 puts "<li>...</li>"
>         end
> end
> puts "</ol>"
> puts "</div>"

<snip>

> So I'm trying to unravel two mysteries:
>
> 1) Why aren't the "yay!"s surrounded by li tags?
> 2) Why are exceptions being raised between each iteration, yet each item
> in the data set being iterated through passes through without exception?

My guess, your method is defined like this:

  class Report
    def to_s
      puts "yay!"
    end
  end

As a result, in each iteration, x.to_s prints "yay!" on it's own line.
Then x.to_s returns nil (the return value of the puts statement) and
"<li>" + nil tries to coerce nil into a String but fails, raising the
exception.

Try redefining your method as such:

  class Report
    def to_s
       "yay!"
    end
  end

Jacob Fugal