vectorTests = testGroup "Vector Tests"
  [ testCase "empty vectors are recognized" testEmptyVector
   , testCase "vectors with elements are recognized" testFilledVector ]
vectorTests = testGroup "Vector Tests"
  [ testCase "empty vectors are recognized" testEmptyVector
   , testCase "vectors with elements are recognized" testFilledVector ]
vectorTests = testGroup "Vector Tests"
  [ testCase "empty vectors are recognized" testEmptyVector
   , testCase "vectors with elements are recognized" testFilledVector ]