I was doing some fizz buzz, and I had this code
pub fn sounder<'a>(div: u32, msg: &'a str) -> impl Fn(u32) -> Option<&'a str>
{
move |n: u32|{
if n % div != 0 {
return None;
};
Some(msg)
}
}
Clippy is telling me that
warning: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> src/lib.rs:1:1
|
1 | / pub fn sounder<'a>(div: u32, msg: &'a str) -> impl Fn(u32) -> Option<&'a str>
2 | | {
3 | | move |n: u32|{
4 | | if n % div != 0 {
... |
9 | | }
10 | | }
| |_^
|
= note: #[warn(clippy::needless_lifetimes)] on by default
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_lifetimes
However, I don't think I can use &'_:
error[E0106]: missing lifetime specifier
--> src/lib.rs:1:67
|
1 | pub fn sounder(div: u32, msg: &'_ str) -> impl Fn(u32) -> Option<&'_ str>
| ^^ help: consider giving it an explicit bounded or 'static lifetime: `'static`
|
= help: this function's return type contains a borrowed value with an elided lifetime, but the lifetime cannot be derived from the arguments
And I certainly can't just elide them:
error[E0106]: missing lifetime specifier
--> src/lib.rs:1:63
|
1 | pub fn sounder(div: u32, msg: &str) -> impl Fn(u32) -> Option<&str>
| ^ help: consider giving it an explicit bounded or 'static lifetime: `&'static`
|
= help: this function's return type contains a borrowed value with an elided lifetime, but the lifetime cannot be derived from the arguments
So, is this a false positive?