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|
#!/usr/bin/env ruby
require 'tins/xt'
$:.unshift 'examples'
require 'recipe_common'
class Cup < Unit; end
class Teaspoon < Unit; end
class Tablespoon < Unit; end
class Flour < Ingredient; end
class Bakingpowder < Ingredient; end
class Salt < Ingredient; end
class Egg < Ingredient; end
class Milk < Ingredient; end
class Butter < Ingredient; end
class Recipe < Tins::BlankSlate.with(:respond_to?, :instance_exec, :inspect, /^deflect/)
include Tins::Deflect
def initialize(&block)
@ingredients = []
deflector = Deflector.new do |number, id, name|
if unit = Unit.unit(name, number)
unit
else
ingredient = Ingredient.ingredient(name, number)
@ingredients << ingredient
end
end
deflect_start(Numeric, :method_missing, deflector)
deflector2 = Deflector.new do |unit, id, name|
ingredient = Ingredient.ingredient(name, unit)
@ingredients << ingredient
end
deflect_start(Unit, :method_missing, deflector2)
instance_exec(&block)
ensure
deflect_stop(Numeric, :method_missing) if deflect?(Numeric, :method_missing)
deflect_stop(Unit, :method_missing) if deflect?(Unit, :method_missing)
end
attr_reader :ingredients
def to_a
@ingredients
end
alias to_ary to_a
def to_s
to_a * "\n"
end
end
class RecipeInterpreter
def recipe(&block)
Recipe.new(&block)
end
end
recipe_source = <<EOT
pancakes = recipe do
2.cups. flour
2.5.teaspoons. baking_powder
0.5.teaspoon. salt
1. egg
1.5.cups. milk
2.tablespoons. butter
end
EOT
pancakes = RecipeInterpreter.new.interpret(recipe_source)
puts pancakes
puts
def recipe(&block)
Recipe.new(&block)
end
pancakes = eval recipe_source
puts pancakes
|
