From: Phrogz <phrogz@...>
Date: 2010-01-13T05:00:05+09:00
Subject: Re: instance_eval with local variable

On Jan 12, 12:23 pm, Phrogz <phr...@mac.com> wrote:
[snip]
> For those interested in second-guessing my approach and coming up with
> a better way to achieve the same end goal
FWIW, there is a workaround I've come up with. Instead of trying to
evaluate the proc in the scope and access instance variables directly,
I can pass the object to the proc and work from its public interface.
My original code is thus changed:

> def self.process_snippets( html )
>   @snippets.inject(html){ |h,(regexp,handler)| h.gsub( regexp, &handler ) }
def self.process_snippets( html, bundle )
  @snippets.inject(html){ |h,(r,proc)| h.gsub(r){ |s| proc
[s,bundle] } }


>   # Mark $$foo$$ as glossary items.
>   DocuBot.handle_snippet /\$\$\w[^$]+\$\$/ do |match|
>     # TODO: look up the glossary term in the bundle's glossary
>     # and insert appropriate text, or flag a new glossary term
>     "<span class='glossary'>#{match[2..-3]}</span>"
>   end
DocuBot.handle_snippet /\$\$\w[^$]+\$\$/ do |match, bundle|
  term = match[2..-3]
  defn = bundle.glossary[term]
  "<span class='glossary' title='#{defn}'>#{term}</span>"
end


I'm thus unblocked in my endeavors, but still interested in the
metaprogramming needed to accomplish my original goal. I was actually
a little surprised that instance_eval doesn't take an arbitrary number
of arguments in the block form and splat them along to the block's
parameters.