Why does one of the same codes get an error and the other doesn't get an error?

Pre-editing

<%@songs.each do|song|%>           
    <div class="col-md-4col-sm-6portfolio-item">       
        <div class="portfolio-caption">           
            <h4class="aaa">%=link_to song.title, song%>br>/h4>      
        </div>
    </div>

Among them, the title method of <%=link_to song.title, song%> is

Edit

<%=link_to @songs.title, song%>← Adding this causes an error
<%@songs.each do | song | %>           
    <div class="col-md-4col-sm-6portfolio-item">       
        <div class="portfolio-caption">           
            <h4class="aaa">%=link_to song.title, song%>br>/h4>      
        </div>
    </div>         
<%end%>

If I do this, I will get the following two errors, but why?

 undefined method `title' for <Song::ActiveRecord_Relation:------>

 title method is not defined

↓song.controller

class SongsController <ApplicationController
  before_action: set_song, only: [:show,:edit,:update,:destroy]
  before_action:authenticate_user!, except:[:index,:show]
  # GET/songs
  # GET/songs.json
  def index
     if params [:user_id]
      @user=User.find(params[:user_id])
      @[email protected](:cached_votes_up=>:desc)
     else
      @songs=Song.all.order(:cached_votes_up=>:desc)
     end
  end

ruby-on-rails ruby

2022-09-29 20:25

1 Answers

@Summary from the comments of Mr. Pork Spout

@ is full-width.
※ If it's full-width, it should be a different error, so I think it's a typo.

@songs is not the Song model, but Song::ActiveRecord_Relation.Since it is a collection, there is no method called title, which must be taken out as a model before using it.
For example, ['abc', 'cdf'].upcase.An aggregate must be treated as an aggregate, and it does not allow the method to fly to its contents.

2022-09-29 20:25

If you have any answers or tips

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