class ActionView::StreamingBuffer

def <<(value)
  value = value.to_s
  value = ERB::Util.h(value) unless value.html_safe?
  @block.call(value)
end

def capture
  buffer = +""
  old_block, @block = @block, ->(value) { buffer << value }
  yield
  buffer.html_safe
ensure
  @block = old_block
end

def html_safe
  self
end

def html_safe?
  true
end

def initialize(block)
  @block = block
end

def raw
  RawStreamingBuffer.new(self)
end

def safe_concat(value)
  @block.call(value.to_s)
end