39 lines
799 B
Text
39 lines
799 B
Text
# Working With Pointers
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## Prefix
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Pointers are returned by the `&` prefix.
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## Examples
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```
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'Base var
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&Base fetch
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#10 &Base store
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#10 &n:inc call
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```
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## Notes
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The use of `&` to get a pointer to a data structure (with a
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word class of `class:data`) is not required. I like to use it
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anyway as it makes my intent a little clearer.
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Pointers are useful with combinators. Consider:
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```
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:abs dup n:negative? [ n:negate ] if ;
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```
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Since the target quote body is a single word, it is more
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efficient to use a pointer instead:
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```
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:abs dup n:negative? &n:negate if ;
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```
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The advantages are speed (saves a level of call/return by
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avoiding the quotation) and size (for the same reason).
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This may be less readable though, so consider the balance
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of performance to readability when using this approach.
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