Add messages to some asserts in std/socket.d

[Flying-Toast]

Work on project #2

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[Flying-Toast]

I'm not sure what the message should be for this assert:

phobos/std/socket.d

Line 970 in 64eac95

assert(result.data.length > 0);

[thewilsonator]

Failed to retrieve AddressInfo? Not surer why thats an assert rather that an ErrnoException (or something a bit more descriptive).

cc @CyberShadow git blame blames you as author of the assert in question. Any insight?

[lesderid]

AFAICT that can never happen, so that assert can probably be removed. Both POSIX[1] and Windows[2] will always return "one or more" results when getaddrinfo returns 0, so that should already be handled by:

phobos/std/socket.d

Line 956 in 64eac95

enforce(ret == 0, new SocketOSException("getaddrinfo error", ret, &formatGaiError));

[1] https://pubs.opengroup.org/onlinepubs/9699919799/functions/getaddrinfo.html
[2] https://docs.microsoft.com/en-us/windows/desktop/api/ws2tcpip/nf-ws2tcpip-getaddrinfo

[Flying-Toast]

I think that

phobos/std/socket.d

Line 271 in 64eac95

static assert(0);

could also be removed, because it is already covered by

phobos/std/socket.d

Line 120 in 64eac95

static assert(0); // No socket support yet.

?

[lesderid]

I think it's better to keep that. If the static assert(0) is removed, what should it return?