Rails 3 - Refactor ruby conditions

Question

I'd like to know if there is a simpler way to do these 2 conditions in ruby :

if params[:action] == 'index' || params[:action] == 'show'

and

if !(comment = (session[:my_params].include?(:comment) rescue nil)).nil?

Thanks in advance

Answer 1

For the first one, you could do:

if %w(index show).include?(params[:action])

The second should really be re-factored into two lines: assignment within a condition check is a code smell; there's never a reason for it.

If you're using Rails / ActiveSupport, you can take advantage of Object#try

comment = session[:my_params].try(:include?, :comment)
if comment
  # ... comment is in scope
end

Otherwise, you're left with something slightly clunkier:

comment = session[:my_params].include?(:comment) rescue nil
if comment
  # etc

Answer 2

1:

if ['index','show'].include? params[:action]

2:

if (comment = (session[:my_params].include?(:comment) rescue nil))

! and .nil? in second condition are redundant

But, really, you should not try to make everything as short as possible, the first thing to care about is how clear your code would be for other people. The second condition should look like:

if ( comment = (session[:my_params] && session[:my_params].include?(:comment) )

or even

comment = session[:my_params] && session[:my_params].include?(:comment)
if comment