How to make cista::get_if<Type> works? about cista HOT 8 CLOSED

Thank you very much for your report.

I hope I fixed it (it's on master):

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I have better issue description from gcc, here below:

quote:
[pointing on "=="]
error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
return v.idx_ == &cista::index_of_type<T, Ts...> ? v.template as()

[pointing on "?"]
error: operands to '?:' have different types 'bool' and 'std::nullptr_t'
return v.idx_ == &cista::index_of_type<T, Ts...> ? v.template as()

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Whoa! That was quick... :)

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Almost :)

It works until recurring reference container is added to the variant, i.e. CISTA::unique_ptr<Test> below:

struct Test;

using Variant = CISTA::variant
	<
	bool,
	std::int64_t,
	std::uint64_t,
	double,
	CISTA::string,
	CISTA::unique_ptr<int>,
	CISTA::unique_ptr<Test>
	>;

struct Test : public CISTA::vector<Variant>
{
};

////////////////////////////////////////////////////////////////////////////////

Variant test{ true };
auto result = cista::get_if<bool>(test);

Same errors on MSVS

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This test case works for me:

TEST_CASE("variant get_if") {
  namespace CISTA = cista::offset;
  struct Test;

  using Variant =
      CISTA::variant<bool, std::int64_t, std::uint64_t, double, CISTA::string,
                     CISTA::unique_ptr<int>, CISTA::unique_ptr<Test>>;

  struct Test : public CISTA::vector<Variant> {};

  Variant test{true};
  auto const result = cista::get_if<bool>(test);
  REQUIRE(result != nullptr);
  CHECK(*result == true);

  test = CISTA::string{"hello test test test test"};
  auto const str = cista::get_if<CISTA::string>(test);
  REQUIRE(str != nullptr);
  CHECK(*str == "hello test test test test");
}

Checking to see if it breaks in GitHub Actions.
da8da3a

Edit: seems the CI build works
https://github.com/felixguendling/cista/actions/runs/1035547916

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btw: cista::get_if<>(const& v) should be also patched:

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Should be fixed now by eb050ae

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Indeed, thank you.

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