Lower _d_arraycast to object.__ArrayCast

[JinShil]

Requires dlang/druntime#2264 to be merged first

[dlang-bot]

Thanks for your pull request, @JinShil!

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[JinShil]

How can I fully qualify this to object.__ArrayCast?

[jacob-carlborg]

Look at how the comparison lowering is done to __cmp.

dmd/src/dmd/expressionsem.d

Lines 9794 to 9798 in 03e7693

	// Lower to object.__cmp(e1, e2)
	Expression al = new IdentifierExp(exp.loc, Id.empty);
	al = new DotIdExp(exp.loc, al, Id.object);
	al = new DotIdExp(exp.loc, al, Id.__cmp);
	al = al.expressionSemantic(sc);

[JinShil]

But I need an Identifer, not an Expression, for the TemplateInstance, later. How do I create a fully-qualified Identifier?

[jacob-carlborg]

How do I create a fully-qualified Identifier?

I don't think that is possible. To get the fully qualified name inside the compiler one needs to walk up the parent chain and build up the name that way. In your case, I think you need to use the overload of the TemplateInstance constructor that takes a TemplateDeclaration. Perhaps you can store the TemplateDeclaration when it's analyzed in the same way as the Object class declaration (and others) is stored:

dmd/src/dmd/dclass.d

Lines 367 to 372 in 03e7693

	if (id == Id.Object)
	{
	if (!inObject)
	error("%s", msg);
	object = this;
	}

[Geod24]

Missing newline

[JinShil]

Fixed.