我刚刚开始研究外部 DSL,但是遇到了一个问题。我写了一个非常简单的测试,我使用 Scala 2.9.0-1 和 scalatest 1.6.1:
class DSLTest extends FlatSpec with ShouldMatchers {
object DSL extends JavaTokenParsers {
def test = stringLiteral
def apply(s: String): Either[String, String] = parseAll(test, s) match {
case Success(tree, _) => Right(tree.toString)
case NoSuccess(msg, _) => Left("Bad syntax: " + msg)
}
}
"DSL" should "parse ABC" in {
val input = "ABC"
DSL(input) match {
case Right(r) =>
r should be === """(ABC)""""
case Left(msg) =>
fail(msg)
}
}
}
如果我运行它,它会在解析过程中失败并返回:
语法错误:字符串匹配正则表达式 `"([^"\p{Cntrl}\\]|\\[\\/bfnrt]|\\u[a-fA-F0-9]{4})*"' 预期但是找到了“A”
任何想法我做错了什么?我基本上遵循了 Dean Wampler 的书(http://ofps.oreilly.com/titles/9780596155957/DomainSpecificLanguages.html)。