[Racket] Dynamically evaluate your language using `make-module-evaluator`

eval.rkt

#lang racket/base

(require racket/sandbox
         racket/runtime-path
         "parser.rkt"
         "tokenizer.rkt"
         "expander.rkt"
         syntax/strip-context)

;; To pass to the module datum
(define-runtime-path expander "expander.rkt")

;; This way, it doesn't matter from what file you evaluate your
;; code, it expands correctly using our expander
(define module-datum `(module m ,expander))

;; I make it a procedure, because `sandbox-namespace-specs`
;; is a list of a thunk followed optionally by module paths
(define (my-sandbox-namespace)
  (namespace-anchor->namespace EXPANDER-ANCHOR))
  
;; you might want to define more module paths with
;; define-runtime-path and add them here
(define allow-for-require (list expander ...))

(define my-mod-eval
  (parameterize ([sandbox-namespace-specs (list my-sandbox-namespace)])
    (make-module-evaluator module-datum
                           #:allow-for-require allow-for-require)))
                           
(define (code-string->syntax str)
  (strip-context
    (parse
      (make-tokenizer
        (open-input-string str)))))
 
;; this should do
(define (my-eval str)
  (define stx (code-string->syntax str))
  (my-mod-eval stx))
 
(provide my-eval)

(module+ test
  (require rackunit)
  (check-pred thing? (my-eval "(thing)"))) ; #t
    

expander.rkt

#lang racket/base

(require ...)

;; this will make possible to use structs gotten from our eval
;; to result in #t when called in struct predicates
(define-namespace-anchor EXPANDER-ANCHOR)

(struct thing ())
(provide (struct-out thing)
         EXPANDER-ANCHOR
         ...)
         

Heads up, I thought I made a mistake and added a warning, but then deleted it. It was another part of the code that I made that was wrong. This code works well. Just in case someone saw the commits of this gist.

Thank you for this.