ruby on rails - ActionView::Template::Error (no implicit conversion of nil into String) -

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i've never gotten error before, , not sure how rid of it.

actionview::template::error (no implicit conversion of nil string) ... 24: <p>genre:<%= link_to @movie.genre, "movies?genre=" + @movie.genre.to_s %></p> .... app/views/movies/show.html.erb:24:in `+'

you need able handle possible nil values. change code :

<p>genre:<%= link_to @movie.try(:genre), "movies?genre=" + @movie.try(:genre) %></p>

since entire link depends on having genre, :

<p>genre:<%= link_to @movie.try(:genre), "movies?genre=" + @movie.try(:genre) if @movie.genre %></p>

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