Newtypes instead of monolithic id

[bors-servo]

Issue by fkaa
Sunday Feb 28, 2016 at 16:40 GMT
Originally opened as servo/cocoa-rs#117

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Is there any reasoning for using traits and implementing them onto id rather than creating newtypes such as struct NSString(id)? I've been running into name collisions with the former a lot lately.

[bors-servo]

Comment by jdm
Sunday Feb 28, 2016 at 18:19 GMT

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I would be in favour of making this change; @pcwalton can you think of any reason not to?

[bors-servo]

Comment by jdm
Sunday May 15, 2016 at 14:55 GMT

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@metajack Any objection here?

[bors-servo]

Comment by metajack
Sunday May 15, 2016 at 16:30 GMT

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This is a question best answered by @pcwalton. It might help in decision making to see a concrete example of how this changes things before and after.

[bors-servo]

Comment by fkaa
Sunday May 15, 2016 at 17:54 GMT

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I've had some success with this inside my own bindings, and I can definitely see the use for this here.

[pcwalton]

I'll start working on this.

[savannidgerinel]

This is also of interest to me, and I would like to know how I can help.

[jdm]

I think the best way to help would be to convert a couple representative modules to use newtypes and make a pull request so we can evaluate the tradeoffs of doing the full conversion. Nobody else is actively looking into it right now.

[savannidgerinel]

Seems simple enough. I could start by converting everything involved with the Hello World app. My attempts are going to be pretty naive to begin with.

I have no experience with Cocoa programming outside of a few tools and an attempt that I made over the weekend of creating a type-safe wrapper around this library.

For memory management purposes, I was turning off the autorelease pool. I'm assuming I need to make the objects part of the Rust borrow system and avoid having the OS deallocate the object IDs that the Rust types are pointing to. Is this reasonable?

[jdm]

I honestly don't have enough Cocoa experience to answer that question, unfortunately. Maybe @jrmuizel does?

[savannidgerinel]

Then I'll just dig in over the next few days, do my best, and let y'all tell me if I've gone wrong.

[savannidgerinel]

I've prototyped this. The process looks long and tedious the way I'm doing it, but I'm also doing it more in the sense of a Rust API instead of mimicking the Objective C API directly. I've created a submodule named cocoa-safe in which I am building in parallel to the cocoa module and in which I have hello_world working, except for the NSRunningApplication object.

https://github.com/savannidgerinel/core-foundation-rs/tree/cocoa-safe

I welcome comments. However, this is probably too big to manage as just a single issue.