从Scala Macro读取typedef的注释

Question

给定一个包装器案例类，它具有一组值，其类型将是带有注释的typedef。我想检查类型以查看注释是否存在以及值是什么。这样我就可以创建一个宏来构建我的case类的实例。

这应该是足够的代码，看看我已经走了多远：

class MyAnnotation(val value: String)

@MyAnnotation("some value")
type MyType = String

case class MyWrapper(myType: MyType)

// macro impl
def impl[T: c.WeakTypeTag](c: blackbox.Context): c.Expr[T] = {
    import c.universe._
    val tpe = weakTypeOf[T]
    val sym = tpe.typeSymbol.asClass
    val cSym = sym.companion
    val cTpe = cSym.typeSignature
    val apply = cTpe.member(TermName("apply")).asMethod
    val applyParamTypes = apply.paramLists.flatten.map(p => p.typeSignature)

    // now I have the types of the parameters to the case class companion object apply method, I want to look at the types (of which they will be typedefs), see if the MyAnnotation annotation is present, and pull out the MyAnnotation.value
}

我正在使用Scala 2.12