HAML 意外实例变量

Question

我正在尝试使用 controller 中定义的引导程序和变量来呈现索引 haml 视图。

播放列表.controller.rb

# frozen_string_literal: true

class PlaylistsController < ApplicationController
  def index
    @playlists = Playlist.all
  end

  # Redirect to the First Screen in the Playlist
  # Use this to setup a Playlist Screen !!
  def show
    playlist = Playlist.find(params[:id])
    playlist_screen = playlist.playlist_screens.first

    redirect_to playlist_screen_path(playlist, playlist_screen.screen)
  end
end

索引.haml

.row
  - playlist in @playlists.each do |playlist|
  .col-lg-2
    .card
      = link_to playlist.name, playlist

但是它似乎无法以某种方式识别变量而且我不明白这里出了什么问题

错误

playlist in @playlists.each do |playlist|
             ^~~~~~~~~~

/home/uralbuntu/Documents/VS/Ruby/screen-rotator/app/views/playlists/index.haml:2: syntax error, unexpected instance variable
 playlist in @playlists.each do |playlist|
             ^~~~~~~~~~
/home/uralbuntu/Documents/VS/Ruby/screen-rotator/app/views/playlists/index.haml:2: syntax error, unexpected instance variable
 playlist in @playlists.each do |playlist|
             ^~~~~~~~~~
/home/uralbuntu/Documents/VS/Ruby/screen-rotator/app/views/playlists/index.haml:2: syntax error, unexpected instance variable
 playlist in @playlists.each do |playlist|
             ^~~~~~~~~~
/home/uralbuntu/Documents/VS/Ruby/screen-rotator/app/views/playlists/index.haml:2: syntax error, unexpected instance variable
 playlist in @playlists.each do |playlist|
             ^~~~~~~~~~
/home/uralbuntu/Documents/VS/Ruby/screen-rotator/app/views/playlists/index.haml:2: syntax error, unexpected instance variable
 playlist in @playlists.each do |playlist|
             ^~~~~~~~~~
/home/uralbuntu/Documents/VS/Ruby/screen-rotator/app/views/playlists/index.haml:2: syntax error, unexpected instance variable
 playlist in @playlists.each do |playlist|
             ^~~~~~~~~~

我也尝试过不使用引导程序，但它给了我同样的错误

Answer 1

该错误与无法找到的变量无关。 这是代码中的语法错误。

只需更改这一行（这不是有效的 Ruby）

- playlist in @playlists.each do |playlist|

进入

- @playlists.each do |playlist|

修复 Ruby 语法错误。