Implement `BindingMode` for pattern matching, so that types can be
correctly inferred using match ergonomics. The binding mode defaults to
`Move` (referred to as 'BindingMode::BindByValue` in rustc), and is
updated by automatic dereferencing of the value being matched.
It was just getting too big. We now have:
- ty: the `Ty` enum and helpers
- ty::infer: actual type inference
- ty::lower: lowering from HIR to `Ty`
- ty::op: helpers for binary operations, currently
I think it'll be better to make the path resolution the number of unresolved
segments, not the first unresolved index; then this error could simply not have
happened. But I'll do that separately.
866: Implement basic support for Associated Methods r=flodiebold a=vipentti
This is my attempt at learning to understand how the type inference works by adding basic support for associated methods. Currently it does not resolve associated types or constants.
The basic idea is that `Resolver::resolve_path` returns a new `PathResult` type, which has two variants, `FullyResolved` and `PartiallyResolved`, fully resolved matches the previous behavior, where as `PartiallyResolved` contains the `PerNs<Resolution` in addition to a `segment_index` which contains the index of the segment which we failed to resolve. This index can then be used to continue inference in `infer_path_expr` using the `Type` we managed to resolve.
This changes some of the previous apis, so looking for feedback and suggestions.
This should enable fixing #832
Co-authored-by: Ville Penttinen <villem.penttinen@gmail.com>
This is done in `infer_path_expr`. When `Resolver::resolve_path` returns
`PartiallyResolved`, we use the returned `Resolution` together with the given
`segment_index` to check if we can find something matching the segment at
segment_index in the impls for that particular type.
This makes it more like the other code model types.
Also make Module::definition_source/declaration_source return HirFileIds, to
make them more like the other source functions.
701: Minor type inference tweaks r=flodiebold a=marcusklaas
Pass down expectation for reference expressions and type the guard in match expressions.
I wasn't able to add a test for the former addition because the type variable previously introduced would always resolve to the right type in the things I tried!
Co-authored-by: Marcus Klaas de Vries <mail@marcusklaas.nl>
