C++20: require implicit conversion for hana::is_convertible by static_cast #492
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In C++20, static_cast can perform aggregate construction (__cpp_aggregate_paren_init). This breaks the example by allowing construction of Employee from its single direct base Person. Change the maybe_static_cast control expression to require implicit conversion. Since this doesn't allow conversion to cv void, add a to_impl for cv void To.
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Of course, this change would disallow |
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Without that patch Visual Studio |
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next developer preview |
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In C++20, static_cast can perform aggregate construction (__cpp_aggregate_paren_init). This breaks the example https://github.com/boostorg/hana/blob/master/example/core/convert/is_convertible.cpp#L13 by allowing construction of Employee from its single direct base Person.
Change the maybe_static_cast control expression to require implicit conversion. Since this doesn't allow conversion to cv void, add a to_impl for cv void To.