Get the model an Active Record object is in

Question

I'm making an ActiveRecord query that joins the contents of each of my models into an array called @contents. But I need to display the content different for data that comes from a specific model.

So in my view I need to perform some sort of test on the elements of my array:

<% @contents.each do |c| %>
  <article>
    <% if [TEST FOR EVENT] %>
      EVENT HTML
    <% elsif [TEST FOR POST] %>
      POST HTML
    <% end %>
  </article>
<% end %>

How do I get the model that c comes from?

score 1 · Accepted Answer · edited May 23 '17 at 12:27

1

This can do the trick:

c.kind_of?(Event) #=> true or false

Going deeper: Ruby: kind_of? vs. instance_of? vs. is_a?

My short version of the comparison:

3.class #=> Fixnum
3.is_a? Integer #=> true
3.kind_of? Integer #=> true
3.instance_of? Integer #=> false
# is_a? & kind_of? can 'detect' subclasses, when instance_of? does not

edited May 23 '17 at 12:27

Community

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1

answered Feb 12 '13 at 19:31

MrYoshiji

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Will accept in 4 mins. Thanks for the reference to the differences between kind_of and is_a and instance_of. – alt Feb 12 '13 at 19:38
1

There's also `case c when Event then ...`. – mu is too short Feb 12 '13 at 20:25

score 1 · Answer 2 · answered Feb 12 '13 at 19:32

1

You can use the is_a? method.

<% if c.is_a?(Event) %> or <% if c.is_a?(Post) %>

Simply pass the class name.

answered Feb 12 '13 at 19:32

Max

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Get the model an Active Record object is in

2 Answers2

Going deeper: Ruby: kind_of? vs. instance_of? vs. is_a?