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copied!<p>You can try to use <a href="http://www.ruby-doc.org/stdlib-1.9.3/libdoc/ostruct/rdoc/OpenStruct.html" rel="nofollow">OpenStruct</a> for this.</p> <blockquote> <p>An OpenStruct is a data structure, similar to a Hash, that allows the definition of arbitrary attributes with their accompanying values. This is accomplished by using Ruby’s metaprogramming to define methods on the class itself.</p> </blockquote> <pre><code>require 'ostruct' (0..10).map { |i| OpenStruct.new(:id => i*10, :name => "#{i*10}%") } # => [#<OpenStruct id=0, name="0%">, #<OpenStruct id=10, name="10%">, ... </code></pre> <p>But if you need a real class, not anonymous class like OpenStruct, then just create this class instances inside the collect/map method:</p> <pre><code>class Ratio attr_reader :id, :name def initialize(id, name) @id = id; @name = name end end (0..10).map { |i| ratio = i*10; Ratio.new(ratio, "#{ratio}%") } # => [#<Ratio: @id=0, @name="0%">, #<Ratio: @id=10, @name="10%">, ... </code></pre> <hr> <p>Maybe I misunderstood you a bit and you want to create this structure not from range, but from array <code>[["0 %", 0], ["10 %", 10], ["20 %", 20], ["30 %", 30]]</code> then the code is similar:</p> <pre><code>require 'ostruct' arr = [["0 %", 0], ["10 %", 10], ["20 %", 20], ["30 %", 30]] p arr.map { |name, id| OpenStruct.new(:id => id, :name => name) } # => [#<OpenStruct id=0, name="0 %">, #<OpenStruct id=10, name="10 %">, #<OpenStruct id=20, name="20 %">, #<OpenStruct id=30, name="30 %">] </code></pre> <hr> <p><strong>UPDATE</strong> I found one corner case in usage of OpenStruct (looks like this is the case for <strong>Ruby 1.8.7</strong> only): <code>OpenStruct#id</code> will return <code>object_id</code> for <code>id</code> instead of field value: </p> <pre><code>ruby-1.8.7-p352 > o = OpenStruct.new :id => 10 => #<OpenStruct id=10> ruby-1.8.7-p352 > o.id (irb):4: warning: Object#id will be deprecated; use Object#object_id => 70021843187380 </code></pre> <p>There are two workarounds: </p> <pre><code># 1. redefine OpenStruct#id method: OpenStruct.__send__(:define_method, :id) { @table[:id] } # 2. dont use 'id' as a value and use any other value: require 'ostruct' (0..10).map { |i| OpenStruct.new(:value => i*10, :name => "#{i*10}%") } # 'value' instead of 'id' ... options_from_collection_for_select(@arr, 'value', 'name') </code></pre> <p>I recommend you to use second approach.</p>

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