Auto merge of #10632 - Alexendoo:needless-maybe-sized, r=Jarcho

Add `needless_maybe_sized` lint

changelog: new lint: [`needless_maybe_sized`]

Closes #10600

tests/ui/auxiliary/proc_macros.rs

@@ -58,7 +58,7 @@ fn group_with_span(delimiter: Delimiter, stream: TokenStream, span: Span) -> Gro
 const ESCAPE_CHAR: char = '$';
 
 /// Takes a single token followed by a sequence of tokens. Returns the sequence of tokens with their
-/// span set to that of the first token. Tokens may be escaped with either `#ident` or `#(tokens)`.
+/// span set to that of the first token. Tokens may be escaped with either `$ident` or `$(tokens)`.
 #[proc_macro]
 pub fn with_span(input: TokenStream) -> TokenStream {
     let mut iter = input.into_iter();
@@ -72,7 +72,7 @@ pub fn with_span(input: TokenStream) -> TokenStream {
 }
 
 /// Takes a sequence of tokens and return the tokens with the span set such that they appear to be
-/// from an external macro. Tokens may be escaped with either `#ident` or `#(tokens)`.
+/// from an external macro. Tokens may be escaped with either `$ident` or `$(tokens)`.
 #[proc_macro]
 pub fn external(input: TokenStream) -> TokenStream {
     let mut res = TokenStream::new();
@@ -84,7 +84,7 @@ pub fn external(input: TokenStream) -> TokenStream {
 }
 
 /// Copies all the tokens, replacing all their spans with the given span. Tokens can be escaped
-/// either by `#ident` or `#(tokens)`.
+/// either by `$ident` or `$(tokens)`.
 fn write_with_span(s: Span, mut input: IntoIter, out: &mut TokenStream) -> Result<()> {
     while let Some(tt) = input.next() {
         match tt {

tests/ui/needless_maybe_sized.fixed

@@ -0,0 +1,116 @@
+//@aux-build:proc_macros.rs
+
+#![allow(unused, clippy::multiple_bound_locations)]
+#![warn(clippy::needless_maybe_sized)]
+
+extern crate proc_macros;
+use proc_macros::external;
+
+fn directly<T: Sized>(t: &T) {}
+
+trait A: Sized {}
+trait B: A {}
+
+fn depth_1<T: A>(t: &T) {}
+fn depth_2<T: B>(t: &T) {}
+
+// We only need to show one
+fn multiple_paths<T: A + B>(t: &T) {}
+
+fn in_where<T>(t: &T)
+where
+    T: Sized,
+{
+}
+
+fn mixed_1<T: Sized>(t: &T)
+{
+}
+
+fn mixed_2<T>(t: &T)
+where
+    T: Sized,
+{
+}
+
+fn mixed_3<T>(t: &T)
+where
+    T: Sized,
+{
+}
+
+struct Struct<T: Sized>(T);
+
+impl<T: Sized> Struct<T> {
+    fn method<U: Sized>(&self) {}
+}
+
+enum Enum<T: Sized + 'static> {
+    Variant(&'static T),
+}
+
+union Union<'a, T: Sized> {
+    a: &'a T,
+}
+
+trait Trait<T: Sized> {
+    fn trait_method<U: Sized>() {}
+
+    type GAT<U: Sized>;
+
+    type Assoc: Sized + ?Sized; // False negative
+}
+
+trait SecondInTrait: Send + Sized {}
+fn second_in_trait<T: SecondInTrait>() {}
+
+fn impl_trait(_: &(impl Sized)) {}
+
+trait GenericTrait<T>: Sized {}
+fn in_generic_trait<T: GenericTrait<U>, U>() {}
+
+mod larger_graph {
+    // C1  C2  Sized
+    //  \  /\  /
+    //   B1  B2
+    //    \  /
+    //     A1
+
+    trait C1 {}
+    trait C2 {}
+    trait B1: C1 + C2 {}
+    trait B2: C2 + Sized {}
+    trait A1: B1 + B2 {}
+
+    fn larger_graph<T: A1>() {}
+}
+
+// Should not lint
+
+fn sized<T: Sized>() {}
+fn maybe_sized<T: ?Sized>() {}
+
+struct SeparateBounds<T: ?Sized>(T);
+impl<T: Sized> SeparateBounds<T> {}
+
+trait P {}
+trait Q: P {}
+
+fn ok_depth_1<T: P + ?Sized>() {}
+fn ok_depth_2<T: Q + ?Sized>() {}
+
+external! {
+    fn in_macro<T: Clone + ?Sized>(t: &T) {}
+
+    fn with_local_clone<T: $Clone + ?Sized>(t: &T) {}
+}
+
+#[derive(Clone)]
+struct InDerive<T: ?Sized> {
+    t: T,
+}
+
+struct Refined<T: ?Sized>(T);
+impl<T: Sized> Refined<T> {}
+
+fn main() {}

tests/ui/needless_maybe_sized.rs

@@ -0,0 +1,119 @@
+//@aux-build:proc_macros.rs
+
+#![allow(unused, clippy::multiple_bound_locations)]
+#![warn(clippy::needless_maybe_sized)]
+
+extern crate proc_macros;
+use proc_macros::external;
+
+fn directly<T: Sized + ?Sized>(t: &T) {}
+
+trait A: Sized {}
+trait B: A {}
+
+fn depth_1<T: A + ?Sized>(t: &T) {}
+fn depth_2<T: B + ?Sized>(t: &T) {}
+
+// We only need to show one
+fn multiple_paths<T: A + B + ?Sized>(t: &T) {}
+
+fn in_where<T>(t: &T)
+where
+    T: Sized + ?Sized,
+{
+}
+
+fn mixed_1<T: Sized>(t: &T)
+where
+    T: ?Sized,
+{
+}
+
+fn mixed_2<T: ?Sized>(t: &T)
+where
+    T: Sized,
+{
+}
+
+fn mixed_3<T>(t: &T)
+where
+    T: Sized,
+    T: ?Sized,
+{
+}
+
+struct Struct<T: Sized + ?Sized>(T);
+
+impl<T: Sized + ?Sized> Struct<T> {
+    fn method<U: Sized + ?Sized>(&self) {}
+}
+
+enum Enum<T: Sized + ?Sized + 'static> {
+    Variant(&'static T),
+}
+
+union Union<'a, T: Sized + ?Sized> {
+    a: &'a T,
+}
+
+trait Trait<T: Sized + ?Sized> {
+    fn trait_method<U: Sized + ?Sized>() {}
+
+    type GAT<U: Sized + ?Sized>;
+
+    type Assoc: Sized + ?Sized; // False negative
+}
+
+trait SecondInTrait: Send + Sized {}
+fn second_in_trait<T: ?Sized + SecondInTrait>() {}
+
+fn impl_trait(_: &(impl Sized + ?Sized)) {}
+
+trait GenericTrait<T>: Sized {}
+fn in_generic_trait<T: GenericTrait<U> + ?Sized, U>() {}
+
+mod larger_graph {
+    // C1  C2  Sized
+    //  \  /\  /
+    //   B1  B2
+    //    \  /
+    //     A1
+
+    trait C1 {}
+    trait C2 {}
+    trait B1: C1 + C2 {}
+    trait B2: C2 + Sized {}
+    trait A1: B1 + B2 {}
+
+    fn larger_graph<T: A1 + ?Sized>() {}
+}
+
+// Should not lint
+
+fn sized<T: Sized>() {}
+fn maybe_sized<T: ?Sized>() {}
+
+struct SeparateBounds<T: ?Sized>(T);
+impl<T: Sized> SeparateBounds<T> {}
+
+trait P {}
+trait Q: P {}
+
+fn ok_depth_1<T: P + ?Sized>() {}
+fn ok_depth_2<T: Q + ?Sized>() {}
+
+external! {
+    fn in_macro<T: Clone + ?Sized>(t: &T) {}
+
+    fn with_local_clone<T: $Clone + ?Sized>(t: &T) {}
+}
+
+#[derive(Clone)]
+struct InDerive<T: ?Sized> {
+    t: T,
+}
+
+struct Refined<T: ?Sized>(T);
+impl<T: Sized> Refined<T> {}
+
+fn main() {}

tests/ui/needless_maybe_sized.stderr

@@ -0,0 +1,353 @@
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:9:24
+   |
+LL | fn directly<T: Sized + ?Sized>(t: &T) {}
+   |                        ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:9:16
+   |
+LL | fn directly<T: Sized + ?Sized>(t: &T) {}
+   |                ^^^^^
+   = note: `-D clippy::needless-maybe-sized` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::needless_maybe_sized)]`
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL - fn directly<T: Sized + ?Sized>(t: &T) {}
+LL + fn directly<T: Sized>(t: &T) {}
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:14:19
+   |
+LL | fn depth_1<T: A + ?Sized>(t: &T) {}
+   |                   ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:14:15
+   |
+LL | fn depth_1<T: A + ?Sized>(t: &T) {}
+   |               ^
+   = note: ...because `A` has the bound `Sized`
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL - fn depth_1<T: A + ?Sized>(t: &T) {}
+LL + fn depth_1<T: A>(t: &T) {}
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:15:19
+   |
+LL | fn depth_2<T: B + ?Sized>(t: &T) {}
+   |                   ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:15:15
+   |
+LL | fn depth_2<T: B + ?Sized>(t: &T) {}
+   |               ^
+   = note: ...because `B` has the bound `A`
+   = note: ...because `A` has the bound `Sized`
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL - fn depth_2<T: B + ?Sized>(t: &T) {}
+LL + fn depth_2<T: B>(t: &T) {}
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:18:30
+   |
+LL | fn multiple_paths<T: A + B + ?Sized>(t: &T) {}
+   |                              ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:18:22
+   |
+LL | fn multiple_paths<T: A + B + ?Sized>(t: &T) {}
+   |                      ^
+   = note: ...because `A` has the bound `Sized`
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL - fn multiple_paths<T: A + B + ?Sized>(t: &T) {}
+LL + fn multiple_paths<T: A + B>(t: &T) {}
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:22:16
+   |
+LL |     T: Sized + ?Sized,
+   |                ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:22:8
+   |
+LL |     T: Sized + ?Sized,
+   |        ^^^^^
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL -     T: Sized + ?Sized,
+LL +     T: Sized,
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:28:8
+   |
+LL |     T: ?Sized,
+   |        ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:26:15
+   |
+LL | fn mixed_1<T: Sized>(t: &T)
+   |               ^^^^^
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL - where
+LL -     T: ?Sized,
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:32:15
+   |
+LL | fn mixed_2<T: ?Sized>(t: &T)
+   |               ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:34:8
+   |
+LL |     T: Sized,
+   |        ^^^^^
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL - fn mixed_2<T: ?Sized>(t: &T)
+LL + fn mixed_2<T>(t: &T)
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:41:8
+   |
+LL |     T: ?Sized,
+   |        ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:40:8
+   |
+LL |     T: Sized,
+   |        ^^^^^
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL -     T: Sized,
+LL -     T: ?Sized,
+LL +     T: Sized,
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:45:26
+   |
+LL | struct Struct<T: Sized + ?Sized>(T);
+   |                          ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:45:18
+   |
+LL | struct Struct<T: Sized + ?Sized>(T);
+   |                  ^^^^^
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL - struct Struct<T: Sized + ?Sized>(T);
+LL + struct Struct<T: Sized>(T);
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:47:17
+   |
+LL | impl<T: Sized + ?Sized> Struct<T> {
+   |                 ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:47:9
+   |
+LL | impl<T: Sized + ?Sized> Struct<T> {
+   |         ^^^^^
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL - impl<T: Sized + ?Sized> Struct<T> {
+LL + impl<T: Sized> Struct<T> {
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:48:26
+   |
+LL |     fn method<U: Sized + ?Sized>(&self) {}
+   |                          ^^^^^^
+   |
+note: `U` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:48:18
+   |
+LL |     fn method<U: Sized + ?Sized>(&self) {}
+   |                  ^^^^^
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL -     fn method<U: Sized + ?Sized>(&self) {}
+LL +     fn method<U: Sized>(&self) {}
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:51:22
+   |
+LL | enum Enum<T: Sized + ?Sized + 'static> {
+   |                      ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:51:14
+   |
+LL | enum Enum<T: Sized + ?Sized + 'static> {
+   |              ^^^^^
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL - enum Enum<T: Sized + ?Sized + 'static> {
+LL + enum Enum<T: Sized + 'static> {
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:55:28
+   |
+LL | union Union<'a, T: Sized + ?Sized> {
+   |                            ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:55:20
+   |
+LL | union Union<'a, T: Sized + ?Sized> {
+   |                    ^^^^^
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL - union Union<'a, T: Sized + ?Sized> {
+LL + union Union<'a, T: Sized> {
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:59:24
+   |
+LL | trait Trait<T: Sized + ?Sized> {
+   |                        ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:59:16
+   |
+LL | trait Trait<T: Sized + ?Sized> {
+   |                ^^^^^
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL - trait Trait<T: Sized + ?Sized> {
+LL + trait Trait<T: Sized> {
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:60:32
+   |
+LL |     fn trait_method<U: Sized + ?Sized>() {}
+   |                                ^^^^^^
+   |
+note: `U` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:60:24
+   |
+LL |     fn trait_method<U: Sized + ?Sized>() {}
+   |                        ^^^^^
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL -     fn trait_method<U: Sized + ?Sized>() {}
+LL +     fn trait_method<U: Sized>() {}
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:62:25
+   |
+LL |     type GAT<U: Sized + ?Sized>;
+   |                         ^^^^^^
+   |
+note: `U` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:62:17
+   |
+LL |     type GAT<U: Sized + ?Sized>;
+   |                 ^^^^^
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL -     type GAT<U: Sized + ?Sized>;
+LL +     type GAT<U: Sized>;
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:68:23
+   |
+LL | fn second_in_trait<T: ?Sized + SecondInTrait>() {}
+   |                       ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:68:32
+   |
+LL | fn second_in_trait<T: ?Sized + SecondInTrait>() {}
+   |                                ^^^^^^^^^^^^^
+   = note: ...because `SecondInTrait` has the bound `Sized`
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL - fn second_in_trait<T: ?Sized + SecondInTrait>() {}
+LL + fn second_in_trait<T: SecondInTrait>() {}
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:70:33
+   |
+LL | fn impl_trait(_: &(impl Sized + ?Sized)) {}
+   |                                 ^^^^^^
+   |
+note: `impl Sized + ?Sized` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:70:25
+   |
+LL | fn impl_trait(_: &(impl Sized + ?Sized)) {}
+   |                         ^^^^^
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL - fn impl_trait(_: &(impl Sized + ?Sized)) {}
+LL + fn impl_trait(_: &(impl Sized)) {}
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:73:42
+   |
+LL | fn in_generic_trait<T: GenericTrait<U> + ?Sized, U>() {}
+   |                                          ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:73:24
+   |
+LL | fn in_generic_trait<T: GenericTrait<U> + ?Sized, U>() {}
+   |                        ^^^^^^^^^^^^^^^
+   = note: ...because `GenericTrait` has the bound `Sized`
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL - fn in_generic_trait<T: GenericTrait<U> + ?Sized, U>() {}
+LL + fn in_generic_trait<T: GenericTrait<U>, U>() {}
+   |
+
+error: `?Sized` bound is ignored because of a `Sized` requirement
+  --> tests/ui/needless_maybe_sized.rs:88:29
+   |
+LL |     fn larger_graph<T: A1 + ?Sized>() {}
+   |                             ^^^^^^
+   |
+note: `T` cannot be unsized because of the bound
+  --> tests/ui/needless_maybe_sized.rs:88:24
+   |
+LL |     fn larger_graph<T: A1 + ?Sized>() {}
+   |                        ^^
+   = note: ...because `A1` has the bound `B2`
+   = note: ...because `B2` has the bound `Sized`
+help: change the bounds that require `Sized`, or remove the `?Sized` bound
+   |
+LL -     fn larger_graph<T: A1 + ?Sized>() {}
+LL +     fn larger_graph<T: A1>() {}
+   |
+
+error: aborting due to 20 previous errors
+

tests/ui/type_repetition_in_bounds.rs

@@ -1,5 +1,9 @@
 #![deny(clippy::type_repetition_in_bounds)]
-#![allow(clippy::extra_unused_type_parameters, clippy::multiple_bound_locations)]
+#![allow(
+    clippy::extra_unused_type_parameters,
+    clippy::multiple_bound_locations,
+    clippy::needless_maybe_sized
+)]
 
 use serde::Deserialize;
 use std::ops::{Add, AddAssign, Div, DivAssign, Mul, MulAssign, Sub, SubAssign};

tests/ui/type_repetition_in_bounds.stderr

@@ -1,5 +1,5 @@
 error: this type has already been used as a bound predicate
-  --> tests/ui/type_repetition_in_bounds.rs:10:5
+  --> tests/ui/type_repetition_in_bounds.rs:14:5
    |
 LL |     T: Clone,
    |     ^^^^^^^^
@@ -12,7 +12,7 @@ LL | #![deny(clippy::type_repetition_in_bounds)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: this type has already been used as a bound predicate
-  --> tests/ui/type_repetition_in_bounds.rs:28:5
+  --> tests/ui/type_repetition_in_bounds.rs:32:5
    |
 LL |     Self: Copy + Default + Ord,
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -20,7 +20,7 @@ LL |     Self: Copy + Default + Ord,
    = help: consider combining the bounds: `Self: Clone + Copy + Default + Ord`
 
 error: this type has already been used as a bound predicate
-  --> tests/ui/type_repetition_in_bounds.rs:103:5
+  --> tests/ui/type_repetition_in_bounds.rs:107:5
    |
 LL |     T: Clone,
    |     ^^^^^^^^
@@ -28,7 +28,7 @@ LL |     T: Clone,
    = help: consider combining the bounds: `T: ?Sized + Clone`
 
 error: this type has already been used as a bound predicate
-  --> tests/ui/type_repetition_in_bounds.rs:109:5
+  --> tests/ui/type_repetition_in_bounds.rs:113:5
    |
 LL |     T: ?Sized,
    |     ^^^^^^^^^
@@ -36,7 +36,7 @@ LL |     T: ?Sized,
    = help: consider combining the bounds: `T: Clone + ?Sized`
 
 error: this type has already been used as a bound predicate
-  --> tests/ui/type_repetition_in_bounds.rs:135:9
+  --> tests/ui/type_repetition_in_bounds.rs:139:9
    |
 LL |         T: Trait<Option<usize>, Box<[String]>, bool> + 'static,
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^