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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.
|
||
|---|---|---|
| .. | ||
| assert | ||
| deriving | ||
| format_foreign | ||
| alloc_error_handler.rs | ||
| asm.rs | ||
| assert.rs | ||
| cfg_accessible.rs | ||
| cfg_eval.rs | ||
| cfg.rs | ||
| cmdline_attrs.rs | ||
| compile_error.rs | ||
| concat_bytes.rs | ||
| concat_idents.rs | ||
| concat.rs | ||
| derive.rs | ||
| edition_panic.rs | ||
| env.rs | ||
| errors.rs | ||
| format_foreign.rs | ||
| format.rs | ||
| global_allocator.rs | ||
| lib.rs | ||
| log_syntax.rs | ||
| offset_of.rs | ||
| proc_macro_harness.rs | ||
| source_util.rs | ||
| standard_library_imports.rs | ||
| test_harness.rs | ||
| test.rs | ||
| trace_macros.rs | ||
| type_ascribe.rs | ||
| util.rs | ||