chervil/lib/chervil/ast/identifier.rb

module Chervil::AST
  class Identifier
    attr_reader :name

    def initialize(name)
      @name = name
    end

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

    def evaluate(env)
      value = env.get(@name)
      if value.nil?
        ::Chervil::Error.new("unbound variable #{@name}")
      else
        value.evaluate(env)
      end
    end
  end
end