class Erubi::CaptureBlockEngine

This engine does not support the :chain_appends option, and ignores it if present.
use a subclass of CaptureBlockEngine::Buffer and override the #| method.
This engine does not support the :escapefunc option. To change the escaping function,
CaptureBlockEngine::Buffer class.
This requires using a string subclass as the buffer value, provided by the
</form>
FOO
<form>
With output being:
end
“<form>#{@bufvar.capture(&block).upcase}</form>”
def upcase_form(&block)
Where upcase_form is defined like:
<% end %>
<%= ‘foo’ %>
<%= upcase_form do %>
An engine class that supports capturing blocks via the <%= and <%== tags:

def add_expression_op(op, code) 

def add_expression_op(op, code)
  check = /\A\s*\z/.send(MATCH_METHOD, code) ? "''" : ''
  with_buffer{@src << op  << check << code}
end

def add_expression_result(code) 

def add_expression_result(code)
  add_expression_op(' <<= ', code)
end

def add_expression_result_escaped(code) 

def add_expression_result_escaped(code)
  add_expression_op(' |= ', code)
end

def initialize(input, properties={}) 

def initialize(input, properties={})
  properties = Hash[properties]
  properties[:bufval] ||= '::Erubi::CaptureBlockEngine::Buffer.new'
  properties[:chain_appends] = false
  super
end