std::experimental::nonesuch
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Defined in header
<experimental/type_traits>
struct nonesuch {
(library fundamentals TS v2)
~nonesuch() = delete;
nonesuch(nonesuch const&) = delete;
void operator=(nonesuch const&) = delete;
std::experimental::nonesuch is a class type used by std::experimental::detected_t to indicate detection failure.
nonesuch has no default constructor or initializer-list constructor, and is not an aggregate.
[edit] Notes
nonesuch cannot be constructed, destroyed, or copied.
[edit] Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior |
|---|---|---|---|
| LWG 2960 | LFTSv2 | nonesuch may be an aggregate and has an implicit conversion sequence from {}
|
made non-aggregate and removed ICS |