class Erubi::CaptureEndEngine

explicitly ending the captures using <%| end %> blocks.
An engine class that supports capturing blocks via the <%|= and <%|== tags,

def handle(indicator, code, tailch, rspace, lspace)

Handle the <%|= and <%|== tags 
def handle(indicator, code, tailch, rspace, lspace)
  case indicator
  when '|=', '|=='
    rspace = nil if tailch && !tailch.empty?
    add_text(lspace) if lspace
    escape_capture = !((indicator == '|=') ^ @escape_capture)
    terminate_expression
    @src << "begin; (#{@bufstack} ||= []) << #{@bufvar}; #{@bufvar} = #{@bufval}; #{@bufstack}.last << #{@escapefunc if escape_capture}((" << code
    @buffer_on_stack = false
    add_text(rspace) if rspace
  when '|'
    rspace = nil if tailch && !tailch.empty?
    add_text(lspace) if lspace
    if @yield_returns_buffer
      terminate_expression
      @src << " #{@bufvar}; "
    end
    @src << code << ")).to_s; ensure; #{@bufvar} = #{@bufstack}.pop; end;"
    @buffer_on_stack = false
    add_text(rspace) if rspace
  else
    super
  end
end

def initialize(input, properties={})

and therefore a different object will be returned.
are cases where the last expression will not be the buffer,
expression. Normally the buffer will be returned anyway, but there
the block, and therefore have the buffer be returned by the yield
<%| end %> tags will have the buffer be the last expression inside
:yield_returns_buffer :: Whether to have <%| tags insert the buffer as an expression, so that
defaults to the same value as :escape.
:escape_capture :: Whether to make <%|= escape by default, and <%|== not escape by default,
additional options:
Initializes the engine. Accepts the same arguments as ::Erubi::Engine, and these 
def initialize(input, properties={})
  properties = Hash[properties]
  escape = properties.fetch(:escape){properties.fetch(:escape_html, false)}
  @escape_capture = properties.fetch(:escape_capture, escape)
  @yield_returns_buffer = properties.fetch(:yield_returns_buffer, false)
  @bufval = properties[:bufval] ||= '::String.new'
  @bufstack = '__erubi_stack'
  properties[:regexp] ||= /<%(\|?={1,2}|-|\#|%|\|)?(.*?)([-=])?%>([ \t]*\r?\n)?/m
  super
end