/ Ruby on Rails
/
method

to_ary

rails latest stable - Class: ActiveRecord::Core
to_ary()
private

+Array#flatten+ will call #to_ary (recursively) on each of the elements of the array, and then rescues from the possible NoMethodError. If those elements are +ActiveRecord::Base+‘s, then this triggers the various method_missing's that we have, which significantly impacts upon performance.

So we can avoid the method_missing hit by explicitly defining #to_ary as nil here.

See also tenderlovemaking.com/2011/06/28/til-its-ok-to-return-nil-from-to_ary.html