mirror of https://gitee.com/bigwinds/arangodb
20 lines
528 B
Plaintext
20 lines
528 B
Plaintext
[#metaprogramming_value]
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[section Template metaprogramming value]
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A ['template metaprogramming value] is a
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[link nullary_metafunction nullary template metafunction] returning itself.
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For example:
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struct void_
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{
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using type = void_;
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};
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This template metaprogramming value is called `void_`. It is a nullary
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metafunction returning itself as its result. Because of this, it can be treated
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as a nullary metafunction and evaluated any number of times. For example
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`void_::type::type::type` is still `void_`.
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[endsect]
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