From: Steve V <ruby@...>
Date: 2005-04-19T06:54:52+09:00
Subject: Store erb block and alter scope of erb block eval?

I tried posting this in the Rails list, and didn't get any responses, so
maybe there's someone here that can help me with my problem.

I'm trying to modularize some display functionality within my Rails app. I
need to be able to store an erb block, and then evaluate it 1 or more times
at a later point in time. Two questions here, which are driving me crazy!

1) How can I store an erb block captured using do for later use? Regular
variable assignment doesn't appear to work.

	def content(&block)
	    @raw_content = block
	end

The above does not work. However, if I evaluate 'block' within the content
method call, then the evaluation works. If I try to evaluate @raw_content at
a later point through another function it just returns nothing. So how
exactly do I store 'block' for later use?

2) When evaluating 'block', how can I get it to use the variables present
within the scope of the calling function, or at least within the calling
class? As it stands now, it will only take variables that have been defined
in the controller, and not my class.

.rhtml file
<%r = Renderer.new()
r.content do%>
	<%=@sometext%>
<%end%>
<%=r.render()%>

.rb file
class SomeController < ApplicationController
    def blah()
		@sometext = "blah"
    end
end

class Renderer
    def content(&block)
		@sometext = "content"
	    buffer = eval("_erbout", block.binding);
		pos = buffer.length
		block.call

		@data = buffer[pos..-1]

		buffer[pos..-1] = ""
	end

	def render()
	    @data
	end
end

The above will render "blah", and not "content", even if the definition of
@sometext is removed from the controller, the eval will not take from the
class.

Any help would be greatly appreciated.

Thanks,
Steve