ruby-on-rails - 在 HAML 上重复打印实例变量

Question

我正在关注本教程（http://ruby.railstutorial.org/chapters/sign-up#sec:signup_form）。然而，当清单 7.23中的代码（转换为 haml）

=if @user.errors.any?
%div{:id => "error_explanation"}
  %div{:class=>"alert alert-error"}
    il modulo contiene errori
    %ul
      = @user.errors.full_messages.each do |msg|
        %li
          = msg

我最终得到了双重打印输出：预期的打印输出，然后是变量的一种打印输出

Name can't be blank
Password is too long (maximum is 15 characters)
["Name can't be blank", "Password is too long (maximum is 15 characters)"]
<h1>Registrazione nuovo utente</h1> <div id='error_explanation'> <div class='alert alert-error'> il modulo contiene errori <ul> <li> Name can't be blank </li> <li> Password is too long (maximum is 15 characters) </li> [&quot;Name can't be blank&quot;, &quot;Password is too long (maximum is 15 characters)&quot;]</ul> </div> </div> 

我对 Rails 编程真的很陌生，但我真的不能。

谢谢， 马塞洛

Answer 1

您的if陈述应以 a 开头-，而不是 a =：

- if @user.errors.any?

你的循环也应该：

- @user.errors.full_messages.each do |msg|

一般来说，如果你试图从 erb 转换为 haml ，<% ... %>就会变成- ...<%= ... %>= ...