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AST evaluation

• Called by someQuery.run
• uses scala.meta to insure AST correctness at compile time

Some info:

• Working with quasiquotes

How should the user define tables?

• annotate classes
  • Doing too much magic behind the scenes confuses IDEs, which reduces usability
• simple inheritance of something like trait Table[T]

How should a tables' primary key be defined?

• By a function?
  Draft:

case class Person(id: Int, name: String) extends Table[Person] { self =>
  override val key = List(self.id)
}

• Warning at compile time, if no key is defined?
  • What implication has this for nested query results?

Quill's AST has no typed nodes ⚠️

• Is there any way to deduct types anyway?
  • Yes, but types of table's columns are at least needed ❗
  • Could Quill provide this? → Related Quill issue

THE BIG ADVENTURE IN REFLECTION WORLD

• typeOf[Person] returns Person as universe.Type
• decls returns us all Members of that type as List[Symbols]
• someSymbol.name returns the name and someSymbol.typeSignature the Type 💃
• to print the Type's name: someType.typeSymbol.name.decodedName.toString

Conclusion

• get Fields' Name:

typeOf[Foo].decls
.map(_.name.decodedName.toString)
.takeWhile(_!="<init>")

• get Fields' Type:

typeOf[Foo].decls
.map(_.typeSignature.typeSymbol.name.decodedName.toString)
.takeWhile(_!="<none>")