Allow multiple message arguments for static assert

[ntrel]

Reboot of #11757 by @thewilsonator.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	17378	enhancement	Allow multiple arguments for assert and static assert

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + dmd#14611"

[tgehr]

I guess one thing that is a bit weird is that this does not expand sequences:

alias Seq(T...)=T;
static assert(false, Seq!("123", "456"));

Idk if it's desirable for pragma(msg, ...), but for static assert it may be confusing. In either case, probably good to add an explicit test case for this to document the intention.

[ntrel]

@tgehr I just tried calling expandTuples(sa.msg); but it doesn't change the array. It has no effect for:

static assert(false, Seq!("123", 456));

[thewilsonator]

I guess one thing that is a bit weird is that this does not expand sequences:

Yeah, Ideally this should behave the same way as pragma(msg, bunch, "of",argu+ments)

[ntrel]

@thewilsonator

I guess one thing that is a bit weird is that this does not expand sequences:

Yeah, Ideally this should behave the same way as pragma(msg, bunch, "of",argu+ments)

This does behave the same:

alias Seq(T...) = T;
pragma(msg, Seq!(int, 0)); // tuple((int), 0)

[ntrel]

@tgehr I just tried calling expandTuples(sa.msg); but it doesn't change the array. It has no effect for:

static assert(false, Seq!("123", 456));

I found out that's because the Seq instantiation gets parsed as a ScopeExp, not a TupleExp (or TypeExp) which expandTuples expects.

[RazvanN7]

Maybe call it msgs?

[RazvanN7]

If this requires many changes it could be left for a subsequent PR.

[ntrel]

@RazvanN7 now done and removed style changes. Also there is a spec PR.

[RazvanN7]

Looks good to me. cc @WalterBright.

Also, mind the spec PR.

[RazvanN7]

@ntrel I assume @WalterBright is busy with other things but I don't think he would oppose this addition. I'm going to go ahead and merge this.

[thewilsonator]

Thanks for getting this in. Should we add a changelog entry for this?

[ntrel]

@thewilsonator Thanks for making it originally ;-) The changelog was included:
https://dlang.org/changelog/pending.html#dmd.static-assert