Rails Locals - Passing Connected Model Data - ruby-on-rails

Question

My model structure is pretty solid. I have MarketingDeliverySystem has_many MarketingSections. MarketingSections has_many MarketingVideos.
I have another segment: GroupDevelopment has_many GroupSections. GroupSections has_many GroupVideos.
I'm trying to use a partial to pass the variables, thus DRYing it all up.
I have the following that I'm trying to pass to the partial:
= render partial: '/sales_presentations/sales_presentation',
locals: { marketing_delivery_system: #marketing_delivery_system,
first_video: first_marketing_video(#marketing_delivery_system),
sales_presentation: #marketing_delivery_system}
Then in the partial I have the following:
.rounded-box-header.blue-bg #{sales_presentation.title}
ul
- sales_presentation.sections.ordered.each_with_index do |section, index|
- list_class = 'section show'
- list_class = 'section hide' if index != 0
li
= link_to section.title, '#', class: 'section', data: { id: section.id }
ul class="#{list_class}" data-section-id="#{section.id}"
- section.videos.ordered.each do |video|
li.video
= link_to video.title, '#',
class: 'video video-link',
data: { video: video.youtube_link,
sales_presentation: sales_presentation.title.parameterize }
.seven.columns
.row
div id="#{sales_presentation.title.parameterize}-container"
video {
id="#{sales_presentation.title.parameterize}-video-player"
class="video-js vjs-default-skin videos"
height=400
poster=""
controls preload='none'
data-default-url="#{first_video(sales_presentation)&.youtube_link}"
I previously had issues with sales_presentation.title at the top until I updated the locals.
My question/issue is how do I pass in through the locals to use for sales_presentation.sections instead to use #marketing_delivery_system.marketing.sections?
I thought I could just put that in through locals:
sales_presentation.sections: #marketing_delivery_system.marketing_sections but I end up with a massive syntax error.
I've also tried creating a partial view for these two and then changed sales_presentation throughout the view to mod. Then changed mod.sections to mod_section and setting that in the locals to mod_section: #marketing_delivery_system.marketing_section. The problem then gets into that I end up needing to hit video later in the iteration. So then that has the same issue.

Answer 1

You misunderstand the meaning of locals in partials.
Says we have
<%= render partial: 'image', locals: {size: #image.size, extension: #image.extension} %>
It means that in image partial now we can use local variable size and extension (keys) as #image.size and #image.extension (values).
Put in locals: {} all local variables you want.
So you can't write in locals sales_presentation.sections: #marketing_delivery_system.marketing.sections
But you can sales_presentation_sections: #marketing_delivery_system.marketing.section
Also you have problem with this code:
locals: { marketing_delivery_system: #marketing_delivery_system,
first_video: first_marketing_video(#marketing_delivery_system),
sales_presentation: #marketing_delivery_system }
marketing_delivery_system and sales_presentation will be with the same value.