for/seq for sequence generating through for loops

for-seq.rkt

#lang racket
(require racket/generator)

(define-syntax (for/seq stx)
  (syntax-case stx ()
    [(_ clauses . body)
     #`(in-generator
        (for/fold/derived #,stx
                          ()
                          clauses
                          (define d (let () . body))
                          (yield d)
                          (values)))]))

(define seq1 (for/seq ([i (in-range 3)]
                       [j (in-list '(a b c))])
               (displayln "here")
               (list j (* i i))))


(define-syntax (for*/seq stx)
  (syntax-case stx ()
    [(_ clauses . body)
     #`(in-generator
        (for*/fold/derived #,stx
                           ()
                           clauses
                           (define d (let () . body))
                           (yield d)
                           (values)))]))


(define seq2 (for*/seq ([i (in-range 3)]
                       [j (in-list '(a b c))])
               (displayln "here")
               (list j (* i i))))