@instance_variable not available inside a ruby block?

It depends on how the block is being called. If it is called using the yield keyword or the Proc#call method, then you'll be able to use your instance variables in the block. If it's called using Object#instance_eval or Module#class_eval then the context of the block will be changed and you won't be able to access your instance variables.

@x = "Outside the class"class Test  def initialize    @x = "Inside the class"  end  def a(&block)    block.call  end  def b(&block)    self.instance_eval(&block)  endendTest.new.a { @x } #=> "Outside the class"Test.new.b { @x } #=> "Inside the class"

In your case, it looks like Sunspot.search is calling your block in a different context using instance_eval, because the block needs easy access to that keywords method.

As Jeremy says, Sunspot executes its search DSL in a new scope.

In order to use an instance variable in the Sunspot.search block, you'll need to pass it an argument. Something like this should work (not tested):

  @q = params[:search][:q] if params[:search]  @search = Sunspot.search(User) do |query|    query.keywords @q  end  @users = @search.results

See here for a better explanation: http://groups.google.com/group/ruby-sunspot/msg/d0444189de3e2725