add `FromStr` Impl for `char`
fixes#24939.
is it possible to use pub(restricted) instead of using a stability attribute for the internal error representation? is it needed at all?
Introduce tidy lint to check for inconsistent tracking issues
This PR
* Refactors the collect_lib_features function to work in a
non-checking mode (no bad pointer needed, and list of
lang features).
* Introduces checking whether unstable/stable tags for a
given feature have inconsistent tracking issues, as in,
multiple tracking issues per feature.
* Fixes such inconsistencies throughout the codebase.
This commit
* Refactors the collect_lib_features function to work in a
non-checking mode (no bad pointer needed, and list of
lang features).
* Introduces checking whether unstable/stable tags for a
given feature have inconsistent tracking issues.
* Fixes such inconsistencies throughout the codebase.
impl Clone for .split_whitespace()
Use custom closure structs for the predicates so that the iterator's
clone can simply be derived. This should also reduce virtual call
overhead by not using function pointers.
Fixes#41655
Use custom closure structs for the predicates so that the iterator's
clone can simply be derived. This should also reduce virtual call
overhead by not using function pointers.
Corrected very minor documentation detail about Unicode and Japanese
Japanese half-width and full-width romaji characters do have upper and lowercase according Unicode (but other Japanese characters do not). For example,
` assert_eq!('\u{FF21}'.to_lowercase().collect::<String>(),"\u{FF41}");`
r? @steveklabnik
It was only accessible through the `#[unstable]` crate std_unicode.
It has never been used in the compiler or standard library
since 47e7a05a28c9662159af2d2e0f2b7efc13fa09cb added it in 2012
“for OS API interop”.
It can be replaced with a one-liner:
```rust
fn is_utf16(slice: &[u16]) -> bool {
std::char::decode_utf16(s.iter().cloned()).all(|r| r.is_ok())
}
```
Remove not(stage0) from deny(warnings)
Historically this was done to accommodate bugs in lints, but there hasn't been a
bug in a lint since this feature was added which the warnings affected. Let's
completely purge warnings from all our stages by denying warnings in all stages.
This will also assist in tracking down `stage0` code to be removed whenever
we're updating the bootstrap compiler.
`BoolTrie` works well for sets of code points spread out through
most of Unicode’s range, but is uses a lot of space for sets
with few, mostly low, code points.
This switches a few of its instances to a similar but simpler trie
data structure.
## Before
`size_of::<BoolTrie>()` is 1552, which is added to
`table.r3.len() * 8 + t.r5.len() + t.r6.len() * 8`:
* `Cc_table`: 1632
* `White_Space_table`: 1656
* `Pattern_White_Space_table`: 1640
* Total: 4928 bytes
## After
`size_of::<SmallBoolTrie>()` is 32, which is added to
`t.r1.len() + t.r2.len() * 8`:
* `Cc_table`: 51
* `White_Space_table`: 273
* `Pattern_White_Space_table`: 193
* Total: 517 bytes
## Difference
Every Rust program with `std` statically linked should be about 4 KB smaller.
Historically this was done to accommodate bugs in lints, but there hasn't been a
bug in a lint since this feature was added which the warnings affected. Let's
completely purge warnings from all our stages by denying warnings in all stages.
This will also assist in tracking down `stage0` code to be removed whenever
we're updating the bootstrap compiler.