29 lines
580 B
Text
29 lines
580 B
Text
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#lang scribble/manual
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@(require (for-label racket))
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@title{RefCopy}
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a reference to the copy of a value@section{categories}
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Core
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@section{description}
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A Ref instance is an object with a single slot named 'value' that serves as a holder of an object.
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RefCopy, in difference to Ref, returns only copies of the value when next is called.
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This can be useful when the original is to be kept unchanged.
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see link::Classes/Ref:: for other methods.
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@section{examples}
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@racketblock[
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a = [1, 2, 3];
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x = RefCopy(a);
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b = x.next;
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b.put(0, 100); // modify b
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a; // a is unchanged.
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]
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