https://github.com/rust-lang/rfcs/pull/221
The current terminology of "task failure" often causes problems when
writing or speaking about code. You often want to talk about the
possibility of an operation that returns a Result "failing", but cannot
because of the ambiguity with task failure. Instead, you have to speak
of "the failing case" or "when the operation does not succeed" or other
circumlocutions.
Likewise, we use a "Failure" header in rustdoc to describe when
operations may fail the task, but it would often be helpful to separate
out a section describing the "Err-producing" case.
We have been steadily moving away from task failure and toward Result as
an error-handling mechanism, so we should optimize our terminology
accordingly: Result-producing functions should be easy to describe.
To update your code, rename any call to `fail!` to `panic!` instead.
Assuming you have not created your own macro named `panic!`, this
will work on UNIX based systems:
grep -lZR 'fail!' . | xargs -0 -l sed -i -e 's/fail!/panic!/g'
You can of course also do this by hand.
[breaking-change]
Some minor wording fixes to the Closures chapter; my brain tripped a few times when reading it, so I tried to come up with something a bit smoother. I’m not a native speaker, so please do review this critically.
This PR changes the signature of several methods from `foo(self, ...)` to `foo(&self, ...)`/`foo(&mut self, ...)`, but there is no breakage of the usage of these methods due to the autoref nature of `method.call()`s. This PR also removes the lifetime parameter from some traits (`Trait<'a>` -> `Trait`). These changes break any use of the extension traits for generic programming, but those traits are not meant to be used for generic programming in the first place. In the whole rust distribution there was only one misuse of a extension trait as a bound, which got corrected (the bound was unnecessary and got removed) as part of this PR.
I've kept the commits as small and self-contained as possible for reviewing sake, but I can squash them when the review is over.
See this [table] to get an idea of what's left to be done. I've already DSTified [`Show`][show] and I'm working on `Hash`, but bootstrapping those changes seem to require a more recent snapshot (#18259 does the trick)
r? @aturon
cc #16918
[show]: https://github.com/japaric/rust/commits/show
[table]: https://docs.google.com/spreadsheets/d/1MZ_iSNuzsoqeS-mtLXnj9m0hBYaH5jI8k9G_Ud8FT5g/edit?usp=sharing
Technically speaking, negative duration is not valid ISO 8601, but we need to
print it anyway. If `d` is a positive duration with the output `xxxxxxx`, then
the expected output of negative `-d` value is `-xxxxxxx`. I.e. the idea is to
print negative durations as positive with a leading minus sign.
Closes#18181.
Avoid O(n^2) performance by reconsidering the full set of obligations only when we are about to report an error (#18208). I found it is still important to consider the full set in order to make tests like `let x: Vec<_> = obligations.iter().collect()` work.
I think we lack the infrastructure to write a regression test for this, but when I did manual testing I found a massive reduction in type-checking time for extreme examples like those found in #18208 vs stage0.
f? @dotdash
This adds impls of Eq/Ord/PartialEq/PartialOrd/Show/Default to Arc<T>, and it
also removes the `Send + Sync` bound on the `Clone` impl of Arc to make it more
deriving-friendly. The `Send + Sync` requirement is still enforce on
construction, of course!
This adds impls of Eq/Ord/PartialEq/PartialOrd/Show/Default to Arc<T>, and it
also removes the `Send + Sync` bound on the `Clone` impl of Arc to make it more
deriving-friendly. The `Send + Sync` requirement is still enforce on
construction, of course!
This allows unboxed closures that reference free type/region parameters to be monomorphized correctly in trans.
It was necessary to make `ty_unboxed_closure` carry around a `Substs` to accomplish this. Plumbing this through typeck revealed several areas where type/region parameters in unboxed closure types are possibly not being handled correctly. Since my goal was just to fix trans, I decided to leave FIXME comments on areas that still need attention and seek feedback on the best way to clean them up, possibly as a follow-up PR.
Closes#16791
This adds a `Substs` field to `ty_unboxed_closure` and plumbs basic
handling of it throughout the compiler. trans now correctly
monomorphizes captured free variables and llvm function defs. This
fixes uses of unboxed closures which reference a free type or region
parameter from their environment in either their signature or free
variables. Closes#16791
