24 lines
545 B
Racket
24 lines
545 B
Racket
#lang scribble/doc
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@(require scribble/manual
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scribble/eval
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"guide-utils.ss")
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@title[#:tag "boxes"]{Boxes}
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A @deftech{box} is like a single-element vector. It prints as
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@litchar{#&} followed by the printed form of the boxed value. A
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@litchar{#&} form can also be used as an expression, but since the
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resulting box is constant, it has practically no use.
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@; So what are boxes good for, anyway?
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@examples[
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(define b (box "apple"))
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b
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(unbox b)
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(set-box! b '(banana boat))
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b
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]
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@refdetails["boxes"]{boxes and box procedures}
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