評論形式不能被渲染

Question

Rails 3中無法呈現某種原因的評論形式，形式是：

<% form_for ([@post.eng_post, @post.eng_post.eng_comments.build]) do |f| %> 

但

<%= debug @post.eng_post.eng_comments.build %> 

給

--- !ruby/object:EngComment 
attributes: 
    id: !!null 
    eng_post_id: 97 
    full_name: !!null 
    website: !!null 
    email: !!null 
    comment: !!null 
    created_at: !!null 
    updated_at: !!null 

型號結構爲：

Posts (have one)-> EngPost (has many)-> EngComments 

（更詳細的模型在這裏Rails 3, comments in a nested form, wrong routes?）

感謝

Answer 1

更換<% form_for與<%= form_for