svoid test_scoreNGramScorer() {
  assertEqualsVerbose(1.0, scoreNGramScorer("abc^e", ll("abcd"), ll("def")));
  assertEqualsVerbose(0.5, scoreNGramScorer("b", ll("abcd"), ll("def")));
  assertEqualsVerbose(0.0, scoreNGramScorer("e^bc", ll("abcd"), ll("def")));
}