Rails partial locals not persisting when sent to another partial as its own local

Question

I render a partial like so:

<%= render :partial => 'widgets/some_partial, :locals => {:foo => 'bar'} %>

So inside of _some_partial.html.erb I render two more partials like so:

<% #foo.nil? #=> false %>
<%= render :partial => 'widgets/another_partial', :locals => {:foo => foo} %>
`<%= render :partial => 'widgets/another_partial_again', :locals => {:foo => foo} %>`

The foo local variable renders fine in some_partial.html.erb and even in another_partial_again.html.erb. However, the foo variable is inaccessible in another_partial.html.erb even though I explicitly passed it in the render call.

What is happening here?

Thanks for the help.

What do you mean by "inaccessible"? Does it throw a `undefined local variable or method` or is it `nil`? Can you show the code that uses `foo` on these sub-partials? — agentofuser, Aug 06 '09 at 17:48

asgeo1 · Answer 1 · 2010-12-14T22:32:01.833

41

I had the undefined local variable or method error come up for me too when I was rendering a partial with :locals defined.

However, I had a different issue causing my problem, so I thought I would share my solution in case it helps anyone else. (This page was the first result when I googled this error after all)

Basically just make sure you use :partial => 'path/to/partial' in your call to render.

I.e.

<%= render :partial => 'widgets/some_partial', :locals => {:foo => 'bar'} %>

NOT like I was doing:

<%= render 'widgets/some_partial', :locals => {:foo => 'bar'} %>

Easy for a rails/ruby newbie like me to miss.

edited Dec 14 '10 at 22:32

answered Dec 05 '10 at 03:09

asgeo1

9,028
6
63
85

6

+1 @asgeo1 Strange that you need `:partial` to make it work, but this does indeed work! – iwasrobbed Apr 11 '11 at 20:31
wow!!! Thanks ... I am just learning Ruby and I was totally confused regarding this error. I wish I could mod-up more points. – Nabheet Feb 12 '12 at 19:04
This solved my issue as well but I'm really curious why the `render partial: "partial_name", locals: { foo: "bar" }` method has to be used. I understand that we are *actually* rendering a partial. What I don't understand is how that differs from a view. – Olivier Lacan Jun 14 '13 at 04:41
still useful in 2015! – rdnewman Jan 31 '15 at 00:36

score 3 · Accepted Answer · answered Aug 06 '09 at 18:03

3

Solved. Turns out I was also rendering the same partial from the controller without sending the proper local variables. Thanks anyways!!!

answered Aug 06 '09 at 18:03

user94154

16,176
20
77
116

1

I actually had the same problem, and my solution was exactly the same -- I figured it out when I saw your mistake :P – Hugo Peixoto Aug 11 '09 at 09:23
ugh me too! ha. I changed my haml from: "- if myvar" to "- if defined?(myvar) && myvar" – Chris Jul 19 '11 at 16:37
same here, was passing the partial in AJAX, forgot to change the symbol – yoshyosh Jan 07 '12 at 02:31

score 0 · Answer 3 · answered Aug 08 '17 at 10:16

Bumped into this very old question cause I faced the same issue. Turned out that with Rails 4+ if you are not using collections or layout the correct way is:

# Instead of <%= render partial: "account", locals: { account: @buyer } %>
<%= render "account", account: @buyer %>

As documented here.

Rails partial locals not persisting when sent to another partial as its own local

3 Answers3