No output from ruby block when return value in method

Here's a trimmed down version of my code:

Helper method:

def render_tree nodes, &block
  bloc开发者_运维百科k.call nodes[1]
  return 0
end

and my HAML file:

    = render_tree @sections do |node|
        - logger.debug("BLOCK CALLED");
        = node.title

The code should print node.title, with the method returning 0. Instead it just prints "0" (the return value).

If I comment out return 0 node.title is printed.

In both situations, the debugger prints "BLOCK CALLED".

I want to print "test" and return 0. What am I doing wrong here?

Edit: So I figure HAML is outputting whatever is returned from the method. The full example is a recursive method that prints out a bunch of stuff. How can I get it to process the HAML instead of just return it?

For starters, if you don't want to print 0(the return value), you have to change this line:

 = render_tree @sections do |node|

to this line:

 - render_tree @sections do |node|

I am not 100% on what you are asking yet...

But, if you want the render_tree method to process the HAML string contained in nodes[1] then you would want to do something like

def render_tree(nodes, &block)
  html = Haml::Engine.new(nodes[1]).render.html_safe
  block.call(html)
end

But, I don't think this will do quite what you are looking for. In part I am confused because your construction doesn't seem very "railsish."

Perhaps with a bit more context it would be clearer?