Refactor object.d: Move __ArrayCast to rt

[JinShil]

Followup to #2634

[n8sh]

Is putting each function in a separate file the direction this is going? One file for __equals, one file for __ArrayCast?

[JinShil]

Is putting each function in a separate file the direction this is going?

No. The idea is to leverage modules and packages as D's unit of encapsulation. Those functions/features/etc. that don't depend on each other should go into their own module.

When I attempt to move dup, __dopostblit, _trustedDup, etc., those would go together in one module, because there is a dependency between them.

Edit: It may turn out that there will basically be one public runtime hook per file, but that is not the motivation. The motivation is encapsulation.

[dlang-bot]

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