Add std::iter::unfold
This adds an **unstable** ~`std::iter::iterate`~ `std::iter::unfold` function and ~`std::iter::Iterate`~ `std::iter::Unfold` type that trivially wrap a ~`FnMut() -> Option<T>`~ `FnMut(&mut State) -> Option<T>` closure to create an iterator. ~Iterator state can be kept in the closure’s environment or captures.~
This is intended to help reduce amount of boilerplate needed when defining an iterator that is only created in one place. Compare the existing example of the `std::iter` module: (explanatory comments elided)
```rust
struct Counter {
count: usize,
}
impl Counter {
fn new() -> Counter {
Counter { count: 0 }
}
}
impl Iterator for Counter {
type Item = usize;
fn next(&mut self) -> Option<usize> {
self.count += 1;
if self.count < 6 {
Some(self.count)
} else {
None
}
}
}
```
… with the same algorithm rewritten to use this new API:
```rust
fn counter() -> impl Iterator<Item=usize> {
std::iter::unfold(0, |count| {
*count += 1;
if *count < 6 {
Some(*count)
} else {
None
}
})
}
```
-----
This also add unstable `std::iter::successors` which takes an (optional) initial item and a closure that takes an item and computes the next one (its successor).
```rust
let powers_of_10 = successors(Some(1_u16), |n| n.checked_mul(10));
assert_eq!(powers_of_10.collect::<Vec<_>>(), &[1, 10, 100, 1_000, 10_000]);
```
Disable some pretty-printers when gdb is rust-enabled
A rust-enabled gdb already knows how to display string slices,
structs, tuples, and enums (and after #54004, the pretty-printers
can't handle enums at all). This patch disables these pretty-printers
when gdb is rust-enabled.
The "gdb-pretty-struct-and-enums-pre-gdb-7-7.rs" test is renamed,
because it does not seem to depend on any behavior of that version of
gdb, and because gdb 7.7 is 4 years old now.
Suggest correct syntax when writing type arg instead of assoc type
- When confusing an associated type with a type argument, suggest the appropriate syntax. Given `Iterator<isize>`, suggest `Iterator<Item = isize>`.
- When encountering multiple missing associated types, emit only one diagnostic.
- Point at associated type def span for context.
- Point at each extra type argument.
Follow up to #48288, fix#20977.
rustc_target: separate out an individual alignment quantity type from Align.
Before this PR, `rustc_target::abi::Align` combined "power-of-two alignment quantity" semantics, with a distinction between ABI (required) and preferred alignment (by having two quantities).
After this PR, `Align` is only *one* such quantity, and a new `AbiAndPrefAlign` type is introduced to hold the pair of ABI and preferred `Align` quantities.
`Align` is used everywhere one quantity is necessary/sufficient, simplifying some of the code in codegen/miri, while `AbiAndPrefAlign` only in layout computation (to propagate preferred alignment).
r? @oli-obk cc @nagisa @RalfJung @nikomatsakis
Issue 56128 segment id ice nightly
Tentative fix for #56128
From what I can tell, the problem is that if you have `pub(super) use foo::{a, b}`, then when we explode the `a` and `b`, the segment ids from the `super` path were not getting cloned. However, once I fixed *that*, then I ran into a problem that the "visibility" node-ids were not present in the final HIR -- this is because the visibility of the "stem" that is returned in this case was getting reset to inherited. I don't *think* it is a problem to undo that, so that the visibility is returned unmodified.
Fixes#55475Fixes#56128
cc @nrc @petrochenkov
Move Cargo.{toml,lock} to the repository root directory.
This should give us back `src/` in errors, panics and debuginfo, for free.
r? @Mark-Simulacrum @alexcrichton cc @michaelwoerister
submodules: update clippy from f5d868c9 to 2f6881c6
Changes:
````
missed another one in the README
run "util/dev update_lints"
rust-lang-nursery/rust-clippy => rust-lang/rust-clippy
Address 'clippy::single-match' dogfood lint
Fix nit
Address travis CI lint failure
Update trivially_copy_pass_by_ref with Trait stderr output
issue#3318 run trivially_copy_pass_by_ref for traits
Update trivially_copy_pass_by_ref with Trait examples
Fix awkward wording
Document how to lint local Clippy changes with locally built Clippy
Enable rustup clippy to refer to the correct documentation
rustup https://github.com/rust-lang/rust/pull/52591
remove unused allow() attributes, NFC
Add regression test
Don't emit suggestion when inside of a macro
````
fixes clippy toolstate
````
missed another one in the README
run "util/dev update_lints"
rust-lang-nursery/rust-clippy => rust-lang/rust-clippy
Address 'clippy::single-match' dogfood lint
Fix nit
Address travis CI lint failure
Update trivially_copy_pass_by_ref with Trait stderr output
issue#3318 run trivially_copy_pass_by_ref for traits
Update trivially_copy_pass_by_ref with Trait examples
Fix awkward wording
Document how to lint local Clippy changes with locally built Clippy
Enable rustup clippy to refer to the correct documentation
rustup https://github.com/rust-lang/rust/pull/52591
remove unused allow() attributes, NFC
Add regression test
Don't emit suggestion when inside of a macro
````
Add SGX target to rustc
This adds the `x86_64-fortanix-unknown-sgx` target specification to the Rust compiler. See #56066 for more details about this target.
Clarifying documentation for collections::hash_map::Entry::or_insert
Previous version does not show that or_insert does not insert the passed value, as the passed value was the same value as what was already in the map.
Return &T / &mut T in ManuallyDrop Deref(Mut) impl
Without this change the generated documentation looks like this:
fn deref(&self) -> &<ManuallyDrop<T> as Deref>::Target
Returning the actual type directly makes the generated docs more clear:
fn deref(&self) -> &T
Basically, compare how the impl for `Box<T>` and `ManuallyDrop<T>` looks in this screenshot:
This is a follow up to 8aa9267 which changed the driver to use lld
directly rather than invoking it through Clang. This change ensures
we pass all the necessary flags to lld.
Doc total order requirement of sort(_unstable)_by
I took the definition of what a total order is from the Ord trait
docs. I specifically put "elements of the slice" because if you
have a slice of f64s, but know none are NaN, then sorting by
partial ord is total in this case. I'm not sure if I should give
such an example in the docs or not.
r? @GuillaumeGomez
This test ensures that everything in `env::vars()` is inherited but
that's not actually true because other tests may add env vars after we
spawn the process, causing the test to be flaky! This commit moves the
test to a run-pass test where it can execute in isolation.
Along the way this removes a lot of the platform specificity of the
test, using iteslf to print the environment instead of a foreign process.
