Ident factory in Quotes

[cchantep]

The Ident type is exposed in Quotes.reflectModule API, but I don't see a function in IdentModule (or elsewhere) provided to create such a value for a term name (is there anything I missed?).

Some simple factory like Ident("foo", ...) would be nice (and seems possible: cchantep@a4c3dcf#diff-42ea4b504ef08605734e689ebe8e3aed413718879873e2eff4951dbed4dc8da0R430 ).

[nicolasstucki]

An alternative is to use Ref.apply.

Before creating an ident it is necessary to resolve to what Symbol or TypeRef it point. That part if the logic belongs to Symbol or TypeRef and not to Ident.

Creating a new symbol an returning an ident will not work and this ident points to a symbol/definition that does not exist in the program (i.e. there is not Definition with that symbol).

[cchantep]

Thanks for your feedback.
I don't see the point about Ref, except if Ref is an Ident under the hood.
For now for example, I don't see about to create a case foo: MyType using CaseDefModule as not being able to create the Ident for the pattern matching.

[nicolasstucki]

Ref will return an Ident or a Select, whichever is the one that is needed.

For now for example, I don't see about to create a case foo: MyType using CaseDefModule as not being able to create the Ident for the pattern matching.

Which Ident?

[nicolasstucki]

To create case foo: MyType => foo you will need something like

      val owner = Symbol.spliceOwner
      val tpe = TypeRepr.of[MyType]
      val bind = Symbol.newBind(owner, "foo", Flags.Case, tpe)
      CaseDef(Bind(bind, Typed(Ref(bind), Inferred(tpe))), None, Ref(bind)))

[cchantep]

Thanks for your feedback. As far as I see, the Bind(..) is not required.
That's such a case that makes me miss quasiquotes ...

[cchantep]

I think there is a similar lack of utility, to resolve a Ident (or whatever Term) for a object/companion (already known as TypeRepr or Symbol).

[cchantep]

BTW it seems weird that to emit a case x: String => () it's not possible to use:

val tpr = TypeRepr.of[String]
val bind =
  Symbol.newBind(
    Symbol.spliceOwner,
    tpr.typeSymbol.name.toLowerCase,
    Flags.Case,
    tpr
  )

val br = Ref(bind)

CaseDef(Typed(br, Inferred(tpr)), guard = None, rhs = UnitConstant())

/* Compilation error:

While expanding a macro, a reference to value string was used outside the scope where it was defined
*/

Indeed it seems required to write the CaseDef as below.

CaseDef(
  Bind(bind, Typed(Wildcard(), Inferred(tpr))),
  guard = None,
  rhs = Block(Nil, Literal(UnitConstant()))
)