How to Require Macros from Untyped Racket in Typed Racket with Dependencies on Typed Imports?

Questions & Answers
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1

How to Require Macros from Untyped Racket in Typed Racket with Dependencies on Typed Imports?

I'm facing an issue when trying to require a macro defined in an untyped Racket
module into a Typed Racket module. The macro depends on a function from the same
untyped module. Here's an example:

Welcome to Racket v8.15 [cs].
> (module m racket
    (provide (all-defined-out))
    (define (g y) y)
    (define-syntax (f stx)
      (syntax-case stx ()
        [(_ x)
         #'(g x)])))
> (require 'm)
> (f 0)
string:7:10: Type Checker: missing type for identifier;
 consider using `require/typed' to import it
  identifier: g
  from module: (quote m)
  in: g
 [,bt for context]
> (require/typed 'm [g (-> Number Number)])
> (g 0)
- : Number
0
> (f 0)
string:7:10: Type Checker: missing type for identifier;
 consider using `require/typed' to import it
  identifier: g
  from module: (quote m)
  in: g
 [,bt for context]

Unfortunately, even though g is typed, f still doesn't recognize the type of
g. However, when f uses built-in functions like add1, it works without any
issues:

Welcome to Racket v8.15 [cs].
> (module m racket
    (provide (all-defined-out))
    (define-syntax (f stx)
      (syntax-case stx ()
        [(_ x)
         #'(add1 x)])))
> (require 'm)
> (f 0)
- : Integer [more precisely: One]
1

Why doesn't the require/typed type information for g propagate to f, and
how can I properly use macros from an untyped Racket module that depend on typed
imports?

2

Your macro is not referring to the g that you imported, it's referring to the g from the definition. (If you write examples in modules it will be clearer.)

The short answer is that there is not a way to make this work, because there's no way to tell Typed Racket about the internals of your module.