regexp.scala

object test {
  def main(args: Array[String]): Unit = {
		val simplePattern = tokenize("abc")
		assert(test("abc", simplePattern))
		assert(test("xabc", simplePattern))
		assert(test("xabcd", simplePattern))
		assert(test("abcd", simplePattern))

		assert(!test("bc", simplePattern))
		assert(!test("ab", simplePattern))

		val orPattern = tokenize("a|b")
		assert(test("a", orPattern))
		assert(test("b", orPattern))
		assert(test("xas", orPattern))
		assert(test("xbs", orPattern))
		assert(test("ab", orPattern))

		assert(!test("d", orPattern))

		val kleenyPattern = tokenize("a*b")
		assert(test("b", kleenyPattern))
		assert(test("ab", kleenyPattern))
		assert(test("aab", kleenyPattern))
		assert(test("aaab", kleenyPattern))

		assert(!test("a", kleenyPattern))
		assert(!test("aa", kleenyPattern))
		assert(!test("xz", kleenyPattern))

		val compositePattern1 = tokenize("a*(c|d)")
		assert(test("c", compositePattern1))
		assert(test("d", compositePattern1))
		assert(test("ac", compositePattern1))
		assert(test("aac", compositePattern1))
		assert(test("aad", compositePattern1))

		assert(!test("a", compositePattern1))
		assert(!test("aa", compositePattern1))
		assert(!test("ab", compositePattern1))
		assert(!test("aab", compositePattern1))


		val compositePattern2 = tokenize("(ab)(cd)*((xz)|(hf))")
		assert(test("abcdxz", compositePattern2))
		assert(test("abcdcdxz", compositePattern2))
		assert(test("abxz", compositePattern2))
		assert(test("abhf", compositePattern2))

		assert(!test("abcd", compositePattern2))
		assert(!test("abc", compositePattern2))
		assert(!test("abkxz", compositePattern2))
		assert(!test("", compositePattern2))
		assert(!test("a", compositePattern2))
		assert(!test("r", compositePattern2))
		assert(!test("xz", compositePattern2))
		assert(!test("hf", compositePattern2))
		assert(!test("cdxz", compositePattern2))
		assert(!test("xz", compositePattern2))

		val kleenyOrPattern = tokenize("x(a|b)*")
		assert(test("xababab", kleenyOrPattern))
		assert(test("x", kleenyOrPattern))
		assert(!test("ss", kleenyOrPattern))
	}
}