How does local_assigns work in Rails?
Ruby on-RailsViewsRuby on-Rails Problem Overview
I've been googling around about this and can't find the right path. I'm working on a Rails app that is using a method called local_assigns. This appears to be something in Rails or a gem, and not specific to my app, but it's used for rendering a partial in different contexts, such as this:
<% if local_assigns[:custom_name] %>
<li><%= custom_name %></li>
<% else %>
or also this:
<%= render "discussions/complementary/#{local_assigns[:action] || params[:action]}" %>
Is this is Rails method? Where can I find more documentation about this?
Ruby on-Rails Solutions
Solution 1 - Ruby on-Rails
local_assigns
is a Rails view helper method that you can check whether this partial has been provided with local variables or not.
Here you render a partial with some values, the headline
and person
will become accessible with predefined value.
<%= render "shared/header", { :headline => "Welcome", :person => person } %>
In shared/header
view:
Headline: <%= headline %>
First name: <%= person.first_name %>
Here is how you check these variables has passed in or not:
<% if local_assigns.has_key? :headline %>
Headline: <%= headline %>
<% end %>
Check this document for more detail on the section Passing local variables to sub templates.