HAML 意外實例變量

Question

我正在嘗試使用 controller 中定義的引導程序和變量來呈現索引 haml 視圖。

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

但是它似乎無法以某種方式識別變量而且我不明白這里出了什么問題

錯誤

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|
             ^~~~~~~~~~

我也嘗試過不使用引導程序，但它給了我同樣的錯誤

Answer 1

該錯誤與無法找到的變量無關。 這是代碼中的語法錯誤。

只需更改這一行（這不是有效的 Ruby）

- playlist in @playlists.each do |playlist|

進入

- @playlists.each do |playlist|

修復 Ruby 語法錯誤。