68 lines
1.3 KiB
Racket
68 lines
1.3 KiB
Racket
#lang scribble/manual
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@(require (for-label racket/base js-maker))
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@title{js-maker Use Cases}
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@author+email["Hans Dijkema" "hans@dijkewijk.nl"]
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@defmodule[js-maker/demo/js-usecases]
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The demos in @filepath{demo/js-usecases.rkt} use only the public
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@racket[js] macro and the compact js-maker 3 form set. They are intentionally
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small: their purpose is to show the supported surface language, not to recreate
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the larger runtime-helper branch.
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@section{Random number}
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@codeblock{
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(js
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(define (randomBetween1And5)
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(return (+ (send Math floor (* (send Math random) 5)) 1))))
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}
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@section{Unique values}
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@codeblock{
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(js
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(define (uniqueValues xs)
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(return (send Array from (new Set xs)))))
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}
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@section{Indexed access}
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@codeblock{
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(js
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(define (arrayAt xs i)
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(return (js-ref xs i))))
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}
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@section{Named let loop}
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@codeblock{
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(js
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(define (sumTo n)
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(let loop ([i 0] [acc 0])
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(if (> i n)
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(return acc)
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(loop (+ i 1) (+ acc i))))))
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}
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@section{Function value}
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@codeblock{
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(js
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(define (makeAdder x)
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(return (lambda (y)
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(return (+ x y))))))
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}
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@section{DOM setter}
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@codeblock{
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(js
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(define (setHtml id html)
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(let ([el (send document getElementById id)])
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(set! (js-dot el innerHTML) html)
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(return (js-dot el innerHTML)))))
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}
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