Enum class improvements for C++17, C++20 and C++23
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Enum class improvements for C++17, C++20 and C++23
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Re: Enum class improvements for C++17, C++20 and C++23
#2[deleted]
Re: Enum class improvements for C++17, C++20 and C++23
#3Union, inheritance, dynamic_cast, enum class, std::variant... when all we needed all along was proper sum types.
Re: Enum class improvements for C++17, C++20 and C++23
#4Speaking of enums, what's a better serialization framework for C++ like Serde in Rust, and then what about Linked Data support and of course also form validation.
Linked Data triples have (subject, predicate, object) and quads have (graph, subject, predicate, object).
RDF has URIs for all Subjects and Predicates.
RDF Objects may be URIs or literal values like xsd:string, xsd:float64, xsd:int (32bit signed value), xsd:integer, xsd:long, xsd:time, xsd:dateTime, xsd:duration.
RDFS then defines Classes and Properties, identified by string URIs.
How best to get from an Enum with (type,attr, {range of values}) to an rdfs:range definition in a schema with a URI prefix?
Python has dataclasses which is newer than attrs, but serde also emits Python pickles
Re: Enum class improvements for C++17, C++20 and C++23
#5Speaking of enums, what's a better serialization framework for C++ like Serde in Rust, and then what about Linked Data support and of course also form validation. Linked Data triples have (subject, predicate, object) and quads have (graph, subject, predicate, object). RDF has URIs for all Subjects and Predicates. RDF Objects may be URIs or literal values like xsd:string, xsd:float64, xsd:int (32bit signed value), xsd…
re Serde: If you want JSON, https://github.com/beached/daw_json_link is about as close as we can get. It interop's well with the reflection(or like) libraries such as Boost Describe or Boost PFR and will work well with std reflection when it is available.
Re: Enum class improvements for C++17, C++20 and C++23
#6> C++20 introduced the `using enum` syntax, which enhances the usability of enums
Out of context, this is a very funny thing to say.
Re: Enum class improvements for C++17, C++20 and C++23
#7Odd that it says
auto value = std::to_underlying(p); // C++23
uint8_t value = static_cast(Permissions::Read);
Re: Enum class improvements for C++17, C++20 and C++23
#8Speaking of enums, what's a better serialization framework for C++ like Serde in Rust, and then what about Linked Data support and of course also form validation. Linked Data triples have (subject, predicate, object) and quads have (graph, subject, predicate, object). RDF has URIs for all Subjects and Predicates. RDF Objects may be URIs or literal values like xsd:string, xsd:float64, xsd:int (32bit signed value), xsd…
So far, most people would use whatever is provided alongside the frameworks they are already using for their application.
Since the 90's, Turbo Vision, OWL, MFC, CSet++, Tools.h++, VCL, ATL, PowerPlant, Qt, Boost, JUCE, Unreal, CryEngine,....
Maybe if reflection does indeed land into C++26, something might be more universally adopted.
Re: Enum class improvements for C++17, C++20 and C++23
#9 enum class Handle : uint32_t { Invalid = 0 };
Handle h { 42 }; // OK
Re: Enum class improvements for C++17, C++20 and C++23
#10Odd that it says auto value = std::to_underlying(p); // C++23 is "more expressive" than uint8_t value = static_cast (Permissions::Read); The latter seems clearly more expressive, not less. You could tighten it up a bit by using auto on the LHS instead of the redundant uint8_t. In the former I don't know what's going on and I have to go read another header to figure out the type of `value`.
The expressibility of a language is what can be expressed in it, not what it can express to you. This additional feature allows you to express this projection without being explicit.