try(), try() again in Rails

In Rails, try() lets you call methods on an object without having to worry about the possibility of that object being nil and thus raising an exception.  Let’s look at some very simple code from a Rails view.

Before

Here’s a simple example of code you might replace with try(). Say you’ve got a Productmodel in your project. A Product may or may not have a known manufacturer, and some links you only want to display if a user is logged in and has administrator rights:

  <!-- products/show.html.erb (before) -->
  <h1><%= @product.name %></h1>

  <% unless @product.manufacturer.nil? %>
    <%= @product.manufacturer.name %>
  <% end %>

  <% if current_user && current_user.is_admin? %>
    <%= link_to 'Edit', edit_product_path(@product) %>
  <% end %>

 try() can help us in a couple of places here: