test  1 ok (\y)
test  2 ok (\y)
test  3 ok (\y)
test  4 ok (\B)
test  5 ok (\B)
test  6 ok (\<)
test  7 ok (\<)
test  8 ok (\>)
test  9 ok (\>)
test 10 ok (\w)
test 11 ok (\w)
test 12 ok (\W)
test 13 ok (\W)
test 14 ok (\`)
test 15 ok (\`)
test 16 ok (\')
test 17 ok (\')