Render an ERB with an instance as the context

gistfile1.rb

require 'erb'

class Context
  attr_accessor :foo
  attr_accessor :bar

  def initialize(foo:, bar:)
    self.foo = foo
    self.bar = bar
  end

  def get_binding
    # as of 1.9.2 Kernel.binding returns the binding of the callsite, so we
    # have to actually call binding from within the instance
    binding
  end
end

context = Context.new(foo: 'hello', bar: 'world')

puts context.inspect

template = <<EOS
foo is "<%= foo %>", and bar is "<%= bar %>"
EOS

erb = ERB.new(template)

puts erb.result(context.get_binding)