alloy/gist:58060

## gistfile1.rb
require "pp"

class Builder
  def initialize
    @elements = []
  end

  %w{ html body h1 ul li }.each do |tag|
    eval %{
      def #{tag}(*args)
        if block_given?
          nested_builder = Builder.new
          yield nested_builder
          @elements << [:#{tag}, nested_builder]
        else
          @elements << [:#{tag}, args]
        end
      end
    }

    def to_s
      @elements.map { |tag, value| "<#{tag}>#{value.to_s}</#{tag}>" }.join
    end
  end
end

mab = Builder.new
mab.html do |h|
  h.body do |b|
    b.h1 "Boats.com has great deals"
    b.ul do |ul|
      ul.li "$49 for a canoe"
      ul.li "$39 for a raft"
      ul.li "$29 for a huge boot that floats and can fit 5 people"
    end
  end
end

pp mab
# #<Builder:0x1b6de0
#  @elements=
#   [[:html,
#     #<Builder:0x1b57c4
#      @elements=
#       [[:body,
#         #<Builder:0x1b574c
#          @elements=
#           [[:h1, ["Boats.com has great deals"]],
#            [:ul,
#             #<Builder:0x1b5698
#              @elements=
#               [[:li, ["$49 for a canoe"]],
#                [:li, ["$39 for a raft"]],
#                [:li,
#                 ["$29 for a huge boot that floats and can fit 5 people"]]]>]]>]]>]]>

p mab.to_s
# "<html><body><h1>Boats.com has great deals</h1><ul><li>$49 for a canoe</li><li>$39 for a raft</li><li>$29 for a huge boot that floats and can fit 5 people</li></ul></body></html>"
	require "pp"

	class Builder
	def initialize
	@elements = []
	end

	%w{ html body h1 ul li }.each do \|tag\|
	eval %{
	def #{tag}(*args)
	if block_given?
	nested_builder = Builder.new
	yield nested_builder
	@elements << [:#{tag}, nested_builder]
	else
	@elements << [:#{tag}, args]
	end
	end
	}

	def to_s
	@elements.map { \|tag, value\| "<#{tag}>#{value.to_s}</#{tag}>" }.join
	end
	end
	end

	mab = Builder.new
	mab.html do \|h\|
	h.body do \|b\|
	b.h1 "Boats.com has great deals"
	b.ul do \|ul\|
	ul.li "$49 for a canoe"
	ul.li "$39 for a raft"
	ul.li "$29 for a huge boot that floats and can fit 5 people"
	end
	end
	end

	pp mab
	# #<Builder:0x1b6de0
	# @elements=
	# [[:html,
	# #<Builder:0x1b57c4
	# @elements=
	# [[:body,
	# #<Builder:0x1b574c
	# @elements=
	# [[:h1, ["Boats.com has great deals"]],
	# [:ul,
	# #<Builder:0x1b5698
	# @elements=
	# [[:li, ["$49 for a canoe"]],
	# [:li, ["$39 for a raft"]],
	# [:li,
	# ["$29 for a huge boot that floats and can fit 5 people"]]]>]]>]]>]]>

	p mab.to_s
	# "<html><body><h1>Boats.com has great deals</h1><ul><li>$49 for a canoe</li><li>$39 for a raft</li><li>$29 for a huge boot that floats and can fit 5 people</li></ul></body></html>"