I’d be interested in some citations; I wasn’t aware of this. Then again it’s not my area of focus, so that’s not super surprising! We don’t do global type inference as a design decision, and since lifetimes are also generic types, I thought this was also the case. I think you can make a compelling argument that this inference would be bad, regardless of possibility.
https://arxiv.org/abs/1803.02796 has a good intro referencing other work. The paper doesn't go into much detail on the borrow checking side of things, but that author is both thoroughly steeped in the linear types research tradition and knows Rust and mentions it a bunch.
The fact that that paper talks about the affine types far more than the lifetimes obliquely illustrates my point in my view, I'm not sure if it's been stated more directly.
So in Rust today type inference strategies are less the point this hinges on. It's more about abolishing the difference between intra-procedural control flow / data flow / whatever, and their inter-procedural equivalents. Similarly, if we had an annotated version of the MIR which was borrow-check correct under composition that would also be good. NLL is great, and starts to clarify what borrow checking is, but running it in "whole" functions makes it to what clear it is a compositional analysis.
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I’d be interested in some citations; I wasn’t aware of this. Then again it’s not my area of focus, so that’s not super surprising! We don’t do global type inference as a design decision, and since lifetimes are also generic types, I thought this was also the case. I think you can make a compelling argument that this inference would be bad, regardless of possibility.
https://arxiv.org/abs/1803.02796 has a good intro referencing other work. The paper doesn't go into much detail on the borrow checking side of things, but that author is both thoroughly steeped in the linear types research tradition and knows Rust and mentions it a bunch.
The fact that that paper talks about the affine types far more than the lifetimes obliquely illustrates my point in my view, I'm not sure if it's been stated more directly.
https://gallium.inria.fr/~fpottier/slides/fpottier-2007-05-l... has some nice history. It wish there is a newer version for things that have been published since, in case the issue is more resolved and I'm out of date.
So in Rust today type inference strategies are less the point this hinges on. It's more about abolishing the difference between intra-procedural control flow / data flow / whatever, and their inter-procedural equivalents. Similarly, if we had an annotated version of the MIR which was borrow-check correct under composition that would also be good. NLL is great, and starts to clarify what borrow checking is, but running it in "whole" functions makes it to what clear it is a compositional analysis.
Thanks!