52 lines
1.2 KiB
C++
52 lines
1.2 KiB
C++
#include <type_traits>
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namespace clanguml {
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//
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// Based on https://github.com/facebook/folly/blob/master/folly/Unit.h
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//
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namespace t00034 {
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struct Void {
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constexpr bool operator==(const Void & /* unused */) const { return true; }
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constexpr bool operator!=(const Void & /* unused */) const { return false; }
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};
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constexpr Void void_t{};
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template <typename T> struct lift_void {
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using type = T;
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};
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template <> struct lift_void<void> {
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using type = Void;
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};
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//
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// TODO: This is a shortcoming of libclang which parses the type of lift_void_t
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// alias as unexposed, i.e. no actual reference to T can be inferred without
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// manually parsing the string 'typename lift_void<T>::type'
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// For now, this test validates that the visitor does not crash, the reference
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// between R and A has to be provided in the configuration file
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//
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template <typename T> using lift_void_t = typename lift_void<T>::type;
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template <typename T> struct drop_void {
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using type = T;
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};
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template <> struct drop_void<Void> {
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using type = void;
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};
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template <typename T> using drop_void_t = typename drop_void<T>::type;
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struct A { };
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struct R {
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lift_void_t<A> *la;
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lift_void_t<void> *lv;
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};
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} // namespace t00034
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} // namespace clanguml
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