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    copied!<p>I'm particularly fond of using <code>method_missing</code>, especially when the code you want to use is very similar across the various method calls. Here's an example from this <a href="http://www.trottercashion.com/2011/02/08/rubys-define_method-method_missing-and-instance_eval.html" rel="noreferrer">site</a> - whenever somebody calls <code>x.boo</code> and <code>boo</code> doesn't exist, method_missing is called with <code>boo</code>, the arguments to <code>boo</code>, and (optionally) a block:</p> <pre><code>class ActiveRecord::Base def method_missing(meth, *args, &amp;block) if meth.to_s =~ /^find_by_(.+)$/ run_find_by_method($1, *args, &amp;block) else super # You *must* call super if you don't handle the # method, otherwise you'll mess up Ruby's method # lookup. end end def run_find_by_method(attrs, *args, &amp;block) # Make an array of attribute names attrs = attrs.split('_and_') # #transpose will zip the two arrays together like so: # [[:a, :b, :c], [1, 2, 3]].transpose # # =&gt; [[:a, 1], [:b, 2], [:c, 3]] attrs_with_args = [attrs, args].transpose # Hash[] will take the passed associative array and turn it # into a hash like so: # Hash[[[:a, 2], [:b, 4]]] # =&gt; { :a =&gt; 2, :b =&gt; 4 } conditions = Hash[attrs_with_args] # #where and #all are new AREL goodness that will find all # records matching our conditions where(conditions).all end end </code></pre> <p><code>define_method</code> also looks like it would work for you, but I have less experience with it than <code>method_missing</code>. Here's the example from the same link:</p> <pre><code>%w(user email food).each do |meth| define_method(meth) { @data[meth.to_sym] } end </code></pre>
 

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