Hi everyone, Below is a reduction of a problem I've noticed when using 'enumerateObjectsUsingBlock' from inside a proc. The line which causes trouble is: [1,2,3].enumerateObjectsUsingBlock( Proc.new { |o, i, s| puts "inner enumeration #{o}" } ) If this line is replaced with: [1,2,3].each { |e| puts "inner enumeration #{e}" } Then the code behaves as expected. framework 'Foundation' proc = Proc.new do |arg| [1,2,3].enumerateObjectsUsingBlock( Proc.new { |o, i, s| puts "inner enumeration #{o}" } ) puts arg.upcase end %w[a b c].enumerateObjectsUsingBlock( Proc.new do |obj, idx, stop| proc.call(obj) end ) The output is as follows: inner enumeration 1 inner enumeration 2 inner enumeration 3 A inner enumeration b inner enumeration c The output I would expect is this: inner enumeration 1 inner enumeration 2 inner enumeration 3 A inner enumeration 1 inner enumeration 2 inner enumeration 3 B inner enumeration 1 inner enumeration 2 inner enumeration 3 C