1.9.3p385 :001 > a=[[1,2,3],[4,5,6],[7,8,9]]
 => [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
1.9.3p385 :002 > a.each_with_index do |row, index, myrow=[], in_block=false|
1.9.3p385 :003 >       p "class: #{row.class}"
1.9.3p385 :004?>     p "value: #{row}"
1.9.3p385 :005?>   end
"class: Array"
"value: [1, 2, 3]"
"class: Array"
"value: [4, 5, 6]"
"class: Array"
"value: [7, 8, 9]"
 => [[1, 2, 3], [4, 5, 6], [7, 8, 9]]

########################################################

1.9.3p385 :006 > a=[[1,2,3],[4,5,6],[7,8,9]]
 => [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
1.9.3p385 :007 > a.each do |row, myrow=[], in_block=false|
1.9.3p385 :008 >       p "class: #{row.class}"
1.9.3p385 :009?>     p "value: #{row}"
1.9.3p385 :010?>   end
"class: Fixnum"
"value: 1"
"class: Fixnum"
"value: 4"
"class: Fixnum"
"value: 7"
 => [[1, 2, 3], [4, 5, 6], [7, 8, 9]]

 #######################################################

1.9.3p385 :011 > a=[[1,2,3],[4,5,6],[7,8,9]]
 => [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
1.9.3p385 :012 > a.each do |row|
1.9.3p385 :013 >       p "class: #{row.class}"
1.9.3p385 :014?>     p "value: #{row}"
1.9.3p385 :015?>   end
"class: Array"
"value: [1, 2, 3]"
"class: Array"
"value: [4, 5, 6]"
"class: Array"
"value: [7, 8, 9]"
 => [[1, 2, 3], [4, 5, 6], [7, 8, 9]]