Racket

js-maker Use Cases🔗ℹ

The demos in "demo/js-usecases.rkt" use only the public js macro and the compact js-maker 3 form set. They are intentionally small: their purpose is to show the supported surface language, not to recreate the larger runtime-helper branch.

1 Random number🔗ℹ

(js
(define (randomBetween1And5)
(return (+ (send Math floor (* (send Math random) 5)) 1))))

2 Unique values🔗ℹ

(js
(define (uniqueValues xs)
(return (send Array from (new Set xs)))))

3 Indexed access🔗ℹ

(js
(define (arrayAt xs i)
(return (js-ref xs i))))

4 Named let loop🔗ℹ

(js
(define (sumTo n)
   (let loop ([i 0] [acc 0])
     (if (> i n)
         (return acc)
         (loop (+ i 1) (+ acc i))))))

5 Function value🔗ℹ

(js
(define (makeAdder x)
(return (lambda (y)
(return (+ x y))))))

6 DOM setter🔗ℹ

(js
(define (setHtml id html)
   (let ([el (send document getElementById id)])
     (set! (js-dot el innerHTML) html)
     (return (js-dot el innerHTML)))))

1	Random number
2	Unique values
3	Indexed access
4	Named let loop
5	Function value
6	DOM setter