expecting tASSOC in a Rails file

I'm sure I've done something stupid here, but I just can't see it.

I call the breadcrumb method in the application view.

app/helpers/breadcrumbs_helper.rb says:

module BreadcrumbsHelper

  def breadcrumb
    @crumb_list = []
    drominay_crumb_builder
    project_crumb_builder
    content_tag(:div, :id => "breadcrumbs", @crumb_list.map { |list_item| crumb_builder(list_item) })
  end

  def crumb_builder(list_item)
    if list_item == @crumb_list.last
      content_tag(:span, list_item['body'], :class => list_item['crumb'])
    else
      body = ["list_item['body']", " → "].join
      link_to(body, list_item['url'], :class => list_item['crumb'])
    end
  end

  def drominay_crumb_builder
    list_item = Hash.new
    list_item['body'] = "Drominay"
    list_item['url'] = "root"
    @crumb_list << list_item
  end

  def project_crumb_builder
  end

end

Why oh why am I getting this "expecting tASSOC" error? (And what is a tASSOC anyway?)

steven-nobles-imac-200:drominay steven$ script/server
=> Booting Mongrel (use 'script/server webrick' to force WEBrick)
=> Rails 2.2.2 application starting on http://0.0.0.0:3000
=> Call with -d to detach
=> Ctrl-C to shutdown server
** Starting Mongrel listening at 0.0.0.0:3000
** Starting Rails with development environment...
Exiting
/Library/Ruby/Site/1.8/rubygems/custom_require.rb:31:in `gem_original_require': /Users/steven/Drominay/app/helpers/breadcrumbs_helper.rb:7: syntax error, unexpected ')', expecting tASSOC (SyntaxError)
/Users/steven/Drominay/app/helpers/breadcrumbs_helper.rb:29: syntax error, unexpected $end, expecting kEND
 from /Library/Ruby/Site/1.8/rubygems/custom_require.rb:31:in `require'
 from /Library/Ruby/Gems/1.8/gems/activesupport-2.2.2/lib/active_support/dependencies.rb:153:in `require'
 from /Library/Ruby/Gems/1.8/gems/activesupport-2.2.2/lib/active_support/dependencies.rb:521:in `new_constants_in'
 from /Libr开发者_运维知识库ary/Ruby/Gems/1.8/gems/activesupport-2.2.2/lib/active_support/dependencies.rb:153:in `require'
 from /Users/steven/Drominay/app/helpers/application_helper.rb:5
 from /Library/Ruby/Gems/1.8/gems/activesupport-2.2.2/lib/active_support/dependencies.rb:382:in `load_without_new_constant_marking'
 from /Library/Ruby/Gems/1.8/gems/activesupport-2.2.2/lib/active_support/dependencies.rb:382:in `load_file'
 from /Library/Ruby/Gems/1.8/gems/activesupport-2.2.2/lib/active_support/dependencies.rb:521:in `new_constants_in'
  ... 56 levels...
 from /Users/steven/.gem/ruby/1.8/gems/rails-2.2.2/lib/commands/server.rb:49
 from /Library/Ruby/Site/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
 from /Library/Ruby/Site/1.8/rubygems/custom_require.rb:31:in `require'
 from script/server:3

---

tASSOC means the => operator

---

It was because I had the arguments for content_tag in the wrong order.

Am still interested in knowing what a tASSOC is, however.