module Chervil::AST
  class Definition
    attr_reader :name
    attr_reader :value

    def initialize(name, value)
      @name = name
      @value = value
    end

    def ==(other)
      @name == other.name && @value == other.value
    end

    def evaluate(env)
      @value = value.evaluate(env) if value.is_a?(Identifier)
      return @value if @value.is_a?(::Chervil::Error)
      env.set(@name.name, @value)
      nil
    end
  end
end