Represent and manipulate IP addresses without providing a port (Socket::IPAddress without a port)

[j8r]

Sometimes we just want to represent an IP address (#10408 reminded me of this issue). This has already caught me in the past to have to put a 0 in a place we just want to represent an IP, where we just want to calculate masks for instance.

Examples of other places which has such type:

• IPAddress ruby gem
• Rust std::net::IpAddr
• Go net.IP
• C# system.net.ipaddress

[j8r]

Go also has TCPAddr and UDPAddr types, which have a port field.

[straight-shoota]

Sure, that could be useful sometimes. But IMO it would not be worth it adding another type, when you can just use Socket::IPAddress with port 0 for example (and ignore port if you only care about the address).

The naming can obviously be confusing. The type is called IPAddress but actually, it consists of the combination of address and port number. This could probably more correctly be called "port", but that would be confusing for similar reasons.

For all practical purposes, I think we're fine with the current situation. It's not ideal, but there's no strictly better solution. And I don't imagine adding another type would be useful for stdlib.

[straight-shoota]

When listing other implementations of such a type, you should also mention if there's also a separate type for the combination with a port number like in Go. If not, our IPAddress is just like the other languages' type, just with the possibility to also specify a port number.

[j8r]

Rust has SocketAddr. C# has IPEndPoint. I don't see anything in Ruby, except Socket.

[j8r]

Yes, indeed calling the object IPAdress is confusing. It doesn't fit its definition
.

I think it would make perfect sense to have a SocketAddress, with a IPAddress and a port field.

The 0 port is a trick, "a la null pointer". At least, the port should be nillable.