module Sinatra::Templates

def render_erb(template, data, options, locals, &block)
  original_out_buf = defined?(@_out_buf) && @_out_buf
  data = data.call if data.kind_of? Proc
  instance = ::ERB.new(data, nil, nil, '@_out_buf')
  locals_assigns = locals.to_a.collect { |k,v| "#{k} = locals[:#{k}]" }
  filename = options.delete(:filename) || '(__ERB__)'
  line = options.delete(:line) || 1
  line -= 1 if instance.src =~ /^#coding:/
  render_binding = binding
  eval locals_assigns.join("\n"), render_binding
  eval instance.src, render_binding, filename, line
  @_out_buf, result = original_out_buf, @_out_buf
  result
end