42 lines
1.1 KiB
C++
42 lines
1.1 KiB
C++
#include "tap.hpp"
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#include "types/tagged.hpp"
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enum tag_t { A, B, C };
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std::ostream& operator<< (std::ostream& os, tag_t val)
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{
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switch (val) {
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case A: return os << "A";
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case B: return os << "B";
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case C: return os << "C";
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}
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unreachable ();
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}
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struct a { static constexpr tag_t tag = A; int value; };
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struct b { static constexpr tag_t tag = B; bool value; };
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struct c { static constexpr tag_t tag = C; unsigned value; };
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int main ()
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{
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cruft::TAP::logger tap;
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// Don't initialise with something that is likely to have a zero tag in
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// case the memory has been pre-emptively or accidentally zeroed.
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cruft::tagged<a,b,c> value (c {.value = 42 });
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tap.expect_eq (value.tag (), c::tag, "initialisation sets the correct tag");
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tap.expect_eq (value.get<c> ().value, 42u, "initialisation saves member variables");
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tap.expect_nothrow ([&] () { value.get<c> (); }, "getter after initialisation succeeds");
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value = a { .value = 7 };
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tap.expect_eq (value.tag (), a::tag, "assignment changes the tag");
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tap.expect_eq (value.get<a> ().value, 7, "assignment saves member variables");
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return tap.status ();
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} |