Add Arguments::as_str().
There exist quite a few macros in the Rust ecosystem which use `format_args!()` for formatting, but special case the one-argument case for optimization:
```rust
#[macro_export]
macro_rules! some_macro {
($s:expr) => { /* print &str directly, no formatting, no buffers */ };
($s:expr, $($tt:tt)*) => { /* use format_args to write to a buffer first */ }
}
```
E.g. [here](
|
||
|---|---|---|
| .. | ||
| assembly | ||
| auxiliary | ||
| codegen | ||
| codegen-units | ||
| compile-fail | ||
| debuginfo | ||
| incremental | ||
| mir-opt | ||
| pretty | ||
| run-make | ||
| run-make-fulldeps | ||
| run-pass-valgrind | ||
| rustdoc | ||
| rustdoc-js | ||
| rustdoc-js-std | ||
| rustdoc-ui | ||
| rustfix | ||
| ui | ||
| ui-fulldeps | ||
| COMPILER_TESTS.md | ||