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22 lines
584 B
Markdown
22 lines
584 B
Markdown
6 years ago
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# Boxes
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A _box_ is like a single-element vector. It can print as a quoted `#&`
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followed by the printed form of the boxed value. A `#&` form can also be
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used as an expression, but since the resulting box is constant, it has
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practically no use.
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Examples:
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```racket
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> (define b (box "apple"))
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> b
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'#&"apple"
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> (unbox b)
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"apple"
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> (set-box! b '(banana boat))
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> b
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'#&(banana boat)
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```
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> +\[missing\] in \[missing\] provides more on boxes and box procedures.
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