# Objective
Fix warnings:
- #[warn(clippy::needless_pass_by_ref_mut)]
- #[warn(elided_lifetimes_in_associated_constant)]
## Solution
- Remove mut
- add &'static
## Errors
```rust
warning: this argument is a mutable reference, but not used mutably
--> crates/bevy_hierarchy/src/child_builder.rs:672:31
|
672 | fn assert_children(world: &mut World, parent: Entity, children: Option<&[Entity]>) {
| ^^^^^^^^^^ help: consider changing to: `&World`
|
= note: this is cfg-gated and may require further changes
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_pass_by_ref_mut
= note: `#[warn(clippy::needless_pass_by_ref_mut)]` on by default
```
```rust
warning: `&` without an explicit lifetime name cannot be used here
--> examples/shader/post_processing.rs:120:21
|
120 | pub const NAME: &str = "post_process";
| ^
|
= warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
= note: for more information, see issue #115010 <https://github.com/rust-lang/rust/issues/115010>
= note: `#[warn(elided_lifetimes_in_associated_constant)]` on by default
help: use the `'static` lifetime
|
120 | pub const NAME: &'static str = "post_process";
| +++++++
```
|
||
|---|---|---|
| .. | ||
| src | ||
| Cargo.toml | ||