Fix Issue 21282 - mixin of AliasSeq "cannot alias an expression"

[BorisCarvajal]

No description provided.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	21282	regression	mixin of AliasSeq "cannot alias an expression"

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 "stable + dmd#11814"

[WalterBright]

@BorisCarvajal looks like your fix is better.

[WalterBright]

Oops, closed the wrong one!

[BorisCarvajal]

You closed that one, xD

[thewilsonator]

Hmm can you repost? Cirrus seems to have died.

[UplinkCoder]

@WalterBright it would have been good, to give tricky internal changes, like this one more eyes to look at.

[CyberShadow]

I noticed that this change allowed more things, possibly more than intended or should be allowed:

struct S
{
	int a, b;
	alias args = typeof(this).tupleof;
}

void main()
{
	S s;
	int i = s.args[0];
}

Generally, getting values through an alias to a field in the type and some implicit context was not possible.