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6b62f37402
Currently a `{D,Subd}iagnosticMessage` can be created from any type that
impls `Into<String>`. That includes `&str`, `String`, and `Cow<'static,
str>`, which are reasonable. It also includes `&String`, which is pretty
weird, and results in many places making unnecessary allocations for
patterns like this:
```
self.fatal(&format!(...))
```
This creates a string with `format!`, takes a reference, passes the
reference to `fatal`, which does an `into()`, which clones the
reference, doing a second allocation. Two allocations for a single
string, bleh.
This commit changes the `From` impls so that you can only create a
`{D,Subd}iagnosticMessage` from `&str`, `String`, or `Cow<'static,
str>`. This requires changing all the places that currently create one
from a `&String`. Most of these are of the `&format!(...)` form
described above; each one removes an unnecessary static `&`, plus an
allocation when executed. There are also a few places where the existing
use of `&String` was more reasonable; these now just use `clone()` at
the call site.
As well as making the code nicer and more efficient, this is a step
towards possibly using `Cow<'static, str>` in
`{D,Subd}iagnosticMessage::{Str,Eager}`. That would require changing
the `From<&'a str>` impls to `From<&'static str>`, which is doable, but
I'm not yet sure if it's worthwhile.
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| .. | ||
| abi | ||
| debuginfo | ||
| driver | ||
| intrinsics | ||
| optimize | ||
| allocator.rs | ||
| analyze.rs | ||
| archive.rs | ||
| base.rs | ||
| cast.rs | ||
| codegen_i128.rs | ||
| common.rs | ||
| compiler_builtins.rs | ||
| concurrency_limiter.rs | ||
| config.rs | ||
| constant.rs | ||
| discriminant.rs | ||
| global_asm.rs | ||
| inline_asm.rs | ||
| lib.rs | ||
| linkage.rs | ||
| main_shim.rs | ||
| num.rs | ||
| pointer.rs | ||
| pretty_clif.rs | ||
| toolchain.rs | ||
| trap.rs | ||
| unsize.rs | ||
| value_and_place.rs | ||
| vtable.rs | ||