Suggest removing `[]` for array of 1 `RangeBounds` arguments.

[IoaNNUwU]

Code

fn main() {
    let mut vec = vec![1, 2, 3];
    vec.drain([..3]);
}

Current output

error[E0277]: the trait bound `[RangeTo<{integer}>; 1]: RangeBounds<usize>` is not satisfied
    --> src\main.rs:5:15
     |
5    |     vec.drain([..3]);
     |         ----- ^^^^^ the trait `RangeBounds<usize>` is not implemented for `[RangeTo<{integer}>; 1]`
     |         |
     |         required by a bound introduced by this call
     |
note: required by a bound in `Vec::<T, A>::drain`
    --> C:\Users\ioann\.rustup\toolchains\stable-x86_64-pc-windows-msvc\lib/rustlib/src/rust\library\alloc\src\vec\mod.rs:2665:12
     |
2663 |     pub fn drain<R>(&mut self, range: R) -> Drain<'_, T, A>
     |            ----- required by a bound in this associated function
2664 |     where
2665 |         R: RangeBounds<usize>,
     |            ^^^^^^^^^^^^^^^^^^ required by this bound in `Vec::<T, A>::drain`

Desired output

`[..3]` is an array of 1 range. Consider removing `[]`.

Rationale and extra context

It's not obvious from the error message why trait bound wasn't satisfied. Rust compiler should probably highlight the fact that [..3] is an array of 1 range, not a range.

Second option may be to impl RangeBounds<T> for [ impl RangeBounds<T> ; 1 ].

Other cases

Rust Version

rustc 1.92.0-nightly (a9d0a6f15 2025-09-16)
binary: rustc
commit-hash: a9d0a6f15533a364816c4d81e2192009ef601d33
commit-date: 2025-09-16
host: x86_64-pc-windows-msvc
release: 1.92.0-nightly
LLVM version: 21.1.1

Anything else?

No response

[IoaNNUwU]

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