Question

对不起，如果它如此明显，我在红宝石上是一个非常棒的人（实际上，编码一般）。此代码用于命名化合物，但在我添加＆＃34; funcao_organica＆＃34;方法，我得到了这个输出：

main.rb：27：语法错误，意外的输入结束，期待keyword_end

我想我已经设定了所有的结局＆＃39;在好地方。这个脚本有什么问题？

class Molecule

  carbon_number_name = { 1 => 'met', 2 => 'et', 3=> 'prop', 4 => 'but', 5 =>'pent', 6 =>'hex'}; bonds = {1 => 'ano', 2 => 'eno', 3 => 'ino'}
  x = Molecule.new

  def molecule(hidrogen, carbon_numbers)
    @carbon_numbers = carbon_numbers
    @hidrogen = hidrogen
    if hidrogen ==  2*(carbon_numbers) 
      return 2
    elsif hidrogen == 2*(carbon_numbers) + 2
      return 1
    elsif hidrogen == 2*(carbon_numbers) - 2
      return 3
    else 
      puts 'this molecule does not exist'

  end  

  def funcao_organica(carbon_main_chain, oxigen)
    @carbon_main_chain = carbon_main_chain
    @oxigen = oxigen 
    if hidrogen == (2*(carbon_numbers) + (carbon_main_chain) - 1) &&  carbon_numbers > 2 
      print 'ol'
    end
  end

  c = 5 ; h = 14 ; r = 5; o = 1
  puts carbon_number_name[c] + bonds[x.molecule(h,c)] + x.funcao_organica(r,o)

end

Answer 1

分子方法中缺少end。结束if语句应该是end：

def molecule(hidrogen, carbon_numbers)
    @carbon_numbers = carbon_numbers
    @hidrogen = hidrogen
    if hidrogen ==  2*(carbon_numbers) 
      return 2
    elsif hidrogen == 2*(carbon_numbers) + 2
      return 1
    elsif hidrogen == 2*(carbon_numbers) - 2
      return 3
    else 
      puts 'this molecule does not exist'
    end #closing the if statement

end

Answer 2

您必须拥有end

def molecule(hidrogen, carbon_numbers)
  @carbon_numbers = carbon_numbers
  @hidrogen = hidrogen
  if hidrogen ==  2*(carbon_numbers) 
    return 2
  elsif hidrogen == 2*(carbon_numbers) + 2
    return 1
  elsif hidrogen == 2*(carbon_numbers) - 2
    return 3
  else 
    puts 'this molecule does not exist'
  end  # <<<=== HERE
end

最后一个end正在关闭方法定义。您还需要另一个end来关闭if。

Answer 3

这里的一个大问题是你的特殊编码风格，尤其是不必要的编码风格使用;将多条线组合在一起并形成不规则的缩进在代码中使用。保持简单，干净，有序，避免制作基本语法错误。作为一个突破，错误在视觉上应该是显而易见的通常的模式。

以下是您的代码的重构版本：

class Molecule
  # Define CONSTANT values for those things that are used more than once
  # within various methods inside your class.
  CARBON_NUMBER_NAME = {
    1 => 'met',
    2 => 'et',
    3=> 'prop',
    4 => 'but',
    5 => 'pent',
    6 => 'hex'
  }
  BONDS = {
    1 => 'ano',
    2 => 'eno',
    3 => 'ino'
  }
  ELEMENT = {
    c: 5,
    h: 14,
    r: 5,
    o: 1
  }

  def molecule(hydrogen, carbon_numbers)
    @carbon_numbers = carbon_numbers
    @hydrogen = hydrogen

    case hydrogen
    when 2*(carbon_numbers) 
      2
    when 2*(carbon_numbers) + 2
      1
    when 2*(carbon_numbers) - 2
      3
    else
      # Raise an error if one occurs, don't just print something.
      raise 'this molecule does not exist'
    end
  end  

  def funcao_organica(carbon_main_chain, oxigen)
    # NOTE: carbon_numbers needs to be defined here, but it isn't,
    #       and @carbon_numbers is only defined if molecule() is
    #       called previously. This could be an issue.
    @carbon_main_chain = carbon_main_chain
    @oxigen = oxigen 

    if hydrogen == (2*(carbon_numbers) + (carbon_main_chain) - 1) &&  carbon_numbers > 2 
      print 'ol'
    end
  end
end

# Move code outside the body of the class definition
x = Molecule.new

puts Molecule::CARBON_NUMBER_NAME[ELEMENT[:c]] + Molecule::BONDS[x.molecule(ELEMENT[:h],ELEMENT[:c])] + x.funcao_organica(ELEMENT[:r],ELEMENT[:o])

＆＃39; end＆＃39;在哪里？失踪？

3 个答案: