review comments

src/librustc_resolve/diagnostics.rs

@@ -1498,20 +1498,20 @@ crate fn add_missing_lifetime_specifiers_label(
                         msg = "consider introducing a named lifetime parameter";
                         should_break = true;
                         match &generics.params {
-                            [] => (generics.span, "<'r>".to_string()),
+                            [] => (generics.span, "<'a>".to_string()),
-                            [param, ..] => (param.span.shrink_to_lo(), "'r, ".to_string()),
+                            [param, ..] => (param.span.shrink_to_lo(), "'a, ".to_string()),
                         }
                     }
                     MissingLifetimeSpot::HRLT { span, span_type } => {
-                        msg = "consider introducing a Higher-Ranked lifetime";
+                        msg = "consider introducing a higher-ranked lifetime";
                         should_break = false;
                         err.note(
-                            "for more information on Higher-Ranked lifetimes, visit \
+                            "for more information on higher-ranked lifetimes, visit \
                              https://doc.rust-lang.org/nomicon/hrtb.html",
                         );
                         let suggestion = match span_type {
-                            HRLTSpanType::Empty => "for<'r> ",
+                            HRLTSpanType::Empty => "for<'a> ",
-                            HRLTSpanType::Tail => ", 'r",
+                            HRLTSpanType::Tail => ", 'a",
                         };
                         (*span, suggestion.to_string())
                     }
@@ -1520,7 +1520,7 @@ crate fn add_missing_lifetime_specifiers_label(
                     if let Ok(snippet) = source_map.span_to_snippet(param.span) {
                         if snippet.starts_with("&") && !snippet.starts_with("&'") {
                             introduce_suggestion
-                                .push((param.span, format!("&'r {}", &snippet[1..])));
+                                .push((param.span, format!("&'a {}", &snippet[1..])));
                         }
                     }
                 }
@@ -1543,13 +1543,13 @@ crate fn add_missing_lifetime_specifiers_label(
                 suggest_existing(err, format!("{}<{}>", snippet, name));
             }
             (0, _, Some("&")) => {
-                suggest_new(err, "&'r ");
+                suggest_new(err, "&'a ");
             }
             (0, _, Some("'_")) => {
-                suggest_new(err, "'r");
+                suggest_new(err, "'a");
             }
             (0, _, Some(snippet)) if !snippet.ends_with(">") => {
-                suggest_new(err, &format!("{}<'r>", snippet));
+                suggest_new(err, &format!("{}<'a>", snippet));
             }
             _ => {
                 err.span_label(span, "expected lifetime parameter");

src/librustc_resolve/lifetimes.rs

@@ -1873,7 +1873,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
                         err.span_suggestion(
                             *span,
                             &format!(
-                                "consider introducing a Higher-Ranked lifetime `{}` here",
+                                "consider introducing a higher-ranked lifetime `{}` here",
                                 lifetime_ref
                             ),
                             match span_type {
@@ -1884,7 +1884,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
                             Applicability::MaybeIncorrect,
                         );
                         err.note(
-                            "for more information on Higher-Ranked lifetimes, visit \
+                            "for more information on higher-ranked lifetimes, visit \
                              https://doc.rust-lang.org/nomicon/hrtb.html",
                         );
                     }

src/test/ui/error-codes/E0106.stderr

@@ -6,8 +6,8 @@ LL |     x: &bool,
    |
 help: consider introducing a named lifetime parameter
    |
-LL | struct Foo<'r> {
+LL | struct Foo<'a> {
-LL |     x: &'r bool,
+LL |     x: &'a bool,
    |
 
 error[E0106]: missing lifetime specifier
@@ -18,9 +18,9 @@ LL |     B(&bool),
    |
 help: consider introducing a named lifetime parameter
    |
-LL | enum Bar<'r> {
+LL | enum Bar<'a> {
 LL |     A(u8),
-LL |     B(&'r bool),
+LL |     B(&'a bool),
    |
 
 error[E0106]: missing lifetime specifier
@@ -31,7 +31,7 @@ LL | type MyStr = &str;
    |
 help: consider introducing a named lifetime parameter
    |
-LL | type MyStr<'r> = &'r str;
+LL | type MyStr<'a> = &'a str;
    |           ^^^^   ^^^
 
 error[E0106]: missing lifetime specifier
@@ -42,8 +42,8 @@ LL |     baz: Baz,
    |
 help: consider introducing a named lifetime parameter
    |
-LL | struct Quux<'r> {
+LL | struct Quux<'a> {
-LL |     baz: Baz<'r>,
+LL |     baz: Baz<'a>,
    |
 
 error[E0106]: missing lifetime specifiers

src/test/ui/impl-header-lifetime-elision/assoc-type.stderr

@@ -6,7 +6,7 @@ LL |     type Output = &i32;
    |
 help: consider introducing a named lifetime parameter
    |
-LL |     type Output<'r> = &'r i32;
+LL |     type Output<'a> = &'a i32;
    |                ^^^^   ^^^
 
 error[E0106]: missing lifetime specifier
@@ -17,7 +17,7 @@ LL |     type Output = &'_ i32;
    |
 help: consider introducing a named lifetime parameter
    |
-LL |     type Output<'r> = &'r i32;
+LL |     type Output<'a> = &'a i32;
    |                ^^^^    ^^
 
 error: aborting due to 2 previous errors

src/test/ui/in-band-lifetimes/issue-61124-anon-lifetime-in-struct-declaration.stderr

@@ -6,7 +6,7 @@ LL | struct Heartbreak(Betrayal);
    |
 help: consider introducing a named lifetime parameter
    |
-LL | struct Heartbreak<'r>(Betrayal<'r>);
+LL | struct Heartbreak<'a>(Betrayal<'a>);
    |                  ^^^^ ^^^^^^^^^^^^
 
 error: aborting due to previous error

src/test/ui/issues/issue-19707.stderr

@@ -11,7 +11,7 @@ LL | type Foo = fn(&u8, &u8) -> &u8;
    |               ^^^  ^^^
 help: consider introducing a named lifetime parameter
    |
-LL | type Foo<'r> = fn(&'r u8, &'r u8) -> &'r u8;
+LL | type Foo<'a> = fn(&'a u8, &'a u8) -> &'a u8;
    |         ^^^^      ^^^^^^  ^^^^^^     ^^^
 
 error[E0106]: missing lifetime specifier
@@ -25,14 +25,14 @@ help: this function's return type contains a borrowed value, but the signature d
    |
 LL | fn bar<F: Fn(&u8, &u8) -> &u8>(f: &F) {}
    |              ^^^  ^^^
-   = note: for more information on Higher-Ranked lifetimes, visit https://doc.rust-lang.org/nomicon/hrtb.html
+   = note: for more information on higher-ranked lifetimes, visit https://doc.rust-lang.org/nomicon/hrtb.html
-help: consider introducing a Higher-Ranked lifetime
+help: consider introducing a higher-ranked lifetime
    |
-LL | fn bar<F: for<'r> Fn(&'r u8, &'r u8) -> &'r u8>(f: &F) {}
+LL | fn bar<F: for<'a> Fn(&'a u8, &'a u8) -> &'a u8>(f: &F) {}
    |           ^^^^^^^    ^^^^^^  ^^^^^^     ^^^
 help: consider introducing a named lifetime parameter
    |
-LL | fn bar<'r, F: Fn(&'r u8, &'r u8) -> &'r u8>(f: &F) {}
+LL | fn bar<'a, F: Fn(&'a u8, &'a u8) -> &'a u8>(f: &F) {}
    |        ^^^       ^^^^^^  ^^^^^^     ^^^
 
 error: aborting due to 2 previous errors

src/test/ui/issues/issue-26638.stderr

@@ -11,7 +11,7 @@ LL | fn parse_type(iter: Box<dyn Iterator<Item=&str>+'static>) -> &str { iter.ne
    |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 help: consider introducing a named lifetime parameter
    |
-LL | fn parse_type<'r>(iter: Box<dyn Iterator<Item=&str>+'static>) -> &'r str { iter.next() }
+LL | fn parse_type<'a>(iter: Box<dyn Iterator<Item=&str>+'static>) -> &'a str { iter.next() }
    |              ^^^^                                                ^^^
 
 error[E0106]: missing lifetime specifier

src/test/ui/issues/issue-30255.stderr

@@ -11,7 +11,7 @@ LL | fn f(a: &S, b: i32) -> &i32 {
    |         ^^
 help: consider introducing a named lifetime parameter
    |
-LL | fn f<'r>(a: &'r S, b: i32) -> &'r i32 {
+LL | fn f<'a>(a: &'a S, b: i32) -> &'a i32 {
    |     ^^^^    ^^^^^             ^^^
 
 error[E0106]: missing lifetime specifier
@@ -27,7 +27,7 @@ LL | fn g(a: &S, b: bool, c: &i32) -> &i32 {
    |         ^^              ^^^^
 help: consider introducing a named lifetime parameter
    |
-LL | fn g<'r>(a: &'r S, b: bool, c: &'r i32) -> &'r i32 {
+LL | fn g<'a>(a: &'a S, b: bool, c: &'a i32) -> &'a i32 {
    |     ^^^^    ^^^^^              ^^^^^^^     ^^^
 
 error[E0106]: missing lifetime specifier
@@ -43,7 +43,7 @@ LL | fn h(a: &bool, b: bool, c: &S, d: &i32) -> &i32 {
    |         ^^^^^              ^^     ^^^^
 help: consider introducing a named lifetime parameter
    |
-LL | fn h<'r>(a: &'r bool, b: bool, c: &'r S, d: &'r i32) -> &'r i32 {
+LL | fn h<'a>(a: &'a bool, b: bool, c: &'a S, d: &'a i32) -> &'a i32 {
    |     ^^^^    ^^^^^^^^              ^^^^^     ^^^^^^^     ^^^
 
 error: aborting due to 3 previous errors

src/test/ui/lifetimes/lifetime-elision-return-type-requires-explicit-lifetime.stderr

@@ -19,7 +19,7 @@ LL | fn g(_x: &isize, _y: &isize) -> &isize {
    |          ^^^^^^      ^^^^^^
 help: consider introducing a named lifetime parameter
    |
-LL | fn g<'r>(_x: &'r isize, _y: &'r isize) -> &'r isize {
+LL | fn g<'a>(_x: &'a isize, _y: &'a isize) -> &'a isize {
    |     ^^^^     ^^^^^^^^^      ^^^^^^^^^     ^^^
 
 error[E0106]: missing lifetime specifier
@@ -35,7 +35,7 @@ LL | fn h(_x: &Foo) -> &isize {
    |          ^^^^
 help: consider introducing a named lifetime parameter
    |
-LL | fn h<'r>(_x: &'r Foo) -> &'r isize {
+LL | fn h<'a>(_x: &'a Foo) -> &'a isize {
    |     ^^^^     ^^^^^^^     ^^^
 
 error[E0106]: missing lifetime specifier

src/test/ui/lifetimes/lifetime-errors/ex1b-return-no-names-if-else.stderr

@@ -11,7 +11,7 @@ LL | fn foo(x: &i32, y: &i32) -> &i32 {
    |           ^^^^     ^^^^
 help: consider introducing a named lifetime parameter
    |
-LL | fn foo<'r>(x: &'r i32, y: &'r i32) -> &'r i32 {
+LL | fn foo<'a>(x: &'a i32, y: &'a i32) -> &'a i32 {
    |       ^^^^    ^^^^^^^     ^^^^^^^     ^^^
 
 error: aborting due to previous error

src/test/ui/proc-macro/item-error.stderr

@@ -6,8 +6,8 @@ LL |     a: &u64
    |
 help: consider introducing a named lifetime parameter
    |
-LL | struct A<'r> {
+LL | struct A<'a> {
-LL |     a: &'r u64
+LL |     a: &'a u64
    |
 
 error: aborting due to previous error

src/test/ui/regions/regions-in-enums-anon.stderr

@@ -6,8 +6,8 @@ LL |     Bar(&isize)
    |
 help: consider introducing a named lifetime parameter
    |
-LL | enum Foo<'r> {
+LL | enum Foo<'a> {
-LL |     Bar(&'r isize)
+LL |     Bar(&'a isize)
    |
 
 error: aborting due to previous error

src/test/ui/regions/regions-in-structs-anon.stderr

@@ -6,8 +6,8 @@ LL |     x: &isize
    |
 help: consider introducing a named lifetime parameter
    |
-LL | struct Foo<'r> {
+LL | struct Foo<'a> {
-LL |     x: &'r isize
+LL |     x: &'a isize
    |
 
 error: aborting due to previous error

src/test/ui/regions/regions-name-undeclared.stderr

@@ -89,12 +89,12 @@ error[E0261]: use of undeclared lifetime name `'b`
 LL | ...                   &'b isize,
    |                        ^^ undeclared lifetime
    |
-   = note: for more information on Higher-Ranked lifetimes, visit https://doc.rust-lang.org/nomicon/hrtb.html
+   = note: for more information on higher-ranked lifetimes, visit https://doc.rust-lang.org/nomicon/hrtb.html
 help: consider introducing lifetime `'b` here
    |
 LL | fn fn_types<'b>(a: &'a isize,
    |            ^^^^
-help: consider introducing a Higher-Ranked lifetime `'b` here
+help: consider introducing a higher-ranked lifetime `'b` here
    |
 LL |             b: Box<dyn for<'a, 'b> FnOnce(&'a isize,
    |                              ^^^^
@@ -105,12 +105,12 @@ error[E0261]: use of undeclared lifetime name `'b`
 LL | ...                   &'b isize)>,
    |                        ^^ undeclared lifetime
    |
-   = note: for more information on Higher-Ranked lifetimes, visit https://doc.rust-lang.org/nomicon/hrtb.html
+   = note: for more information on higher-ranked lifetimes, visit https://doc.rust-lang.org/nomicon/hrtb.html
 help: consider introducing lifetime `'b` here
    |
 LL | fn fn_types<'b>(a: &'a isize,
    |            ^^^^
-help: consider introducing a Higher-Ranked lifetime `'b` here
+help: consider introducing a higher-ranked lifetime `'b` here
    |
 LL |             b: Box<dyn for<'a, 'b> FnOnce(&'a isize,
    |                              ^^^^

src/test/ui/suggestions/fn-missing-lifetime-in-item.stderr

@@ -4,12 +4,12 @@ error[E0261]: use of undeclared lifetime name `'a`
 LL | struct S1<F: Fn(&i32, &i32) -> &'a i32>(F);
    |                                 ^^ undeclared lifetime
    |
-   = note: for more information on Higher-Ranked lifetimes, visit https://doc.rust-lang.org/nomicon/hrtb.html
+   = note: for more information on higher-ranked lifetimes, visit https://doc.rust-lang.org/nomicon/hrtb.html
 help: consider introducing lifetime `'a` here
    |
 LL | struct S1<'a, F: Fn(&i32, &i32) -> &'a i32>(F);
    |           ^^^
-help: consider introducing a Higher-Ranked lifetime `'a` here
+help: consider introducing a higher-ranked lifetime `'a` here
    |
 LL | struct S1<F: for<'a> Fn(&i32, &i32) -> &'a i32>(F);
    |              ^^^^^^^
@@ -25,14 +25,14 @@ help: this function's return type contains a borrowed value, but the signature d
    |
 LL | struct S2<F: Fn(&i32, &i32) -> &i32>(F);
    |                 ^^^^  ^^^^
-   = note: for more information on Higher-Ranked lifetimes, visit https://doc.rust-lang.org/nomicon/hrtb.html
+   = note: for more information on higher-ranked lifetimes, visit https://doc.rust-lang.org/nomicon/hrtb.html
-help: consider introducing a Higher-Ranked lifetime
+help: consider introducing a higher-ranked lifetime
    |
-LL | struct S2<F: for<'r> Fn(&'r i32, &'r i32) -> &'r i32>(F);
+LL | struct S2<F: for<'a> Fn(&'a i32, &'a i32) -> &'a i32>(F);
    |              ^^^^^^^    ^^^^^^^  ^^^^^^^     ^^^
 help: consider introducing a named lifetime parameter
    |
-LL | struct S2<'r, F: Fn(&'r i32, &'r i32) -> &'r i32>(F);
+LL | struct S2<'a, F: Fn(&'a i32, &'a i32) -> &'a i32>(F);
    |           ^^^       ^^^^^^^  ^^^^^^^     ^^^
 
 error[E0582]: binding for associated type `Output` references lifetime `'a`, which does not appear in the trait input types

src/test/ui/unboxed-closures/unboxed-closure-sugar-lifetime-elision.stderr

@@ -11,7 +11,7 @@ LL |     let _: dyn Foo(&isize, &usize) -> &usize;
    |                    ^^^^^^  ^^^^^^
 help: consider introducing a named lifetime parameter
    |
-LL | fn main<'r>() {
+LL | fn main<'a>() {
 LL |     eq::< dyn for<'a> Foo<(&'a isize,), Output=&'a isize>,
 LL |           dyn Foo(&isize) -> &isize                                   >();
 LL |     eq::< dyn for<'a> Foo<(&'a isize,), Output=(&'a isize, &'a isize)>,

src/test/ui/underscore-lifetime/dyn-trait-underscore-in-struct.stderr

@@ -6,8 +6,8 @@ LL |     x: Box<dyn Debug + '_>,
    |
 help: consider introducing a named lifetime parameter
    |
-LL | struct Foo<'r> {
+LL | struct Foo<'a> {
-LL |     x: Box<dyn Debug + 'r>,
+LL |     x: Box<dyn Debug + 'a>,
    |
 
 error[E0228]: the lifetime bound for this object type cannot be deduced from context; please supply an explicit bound

src/test/ui/underscore-lifetime/in-fn-return-illegal.stderr

@@ -11,7 +11,7 @@ LL | fn foo(x: &u32, y: &u32) -> &'_ u32 { loop { } }
    |           ^^^^     ^^^^
 help: consider introducing a named lifetime parameter
    |
-LL | fn foo<'r>(x: &'r u32, y: &'r u32) -> &'r u32 { loop { } }
+LL | fn foo<'a>(x: &'a u32, y: &'a u32) -> &'a u32 { loop { } }
    |       ^^^^    ^^^^^^^     ^^^^^^^      ^^
 
 error: aborting due to previous error

src/test/ui/underscore-lifetime/in-struct.stderr

@@ -6,8 +6,8 @@ LL |     x: &'_ u32,
    |
 help: consider introducing a named lifetime parameter
    |
-LL | struct Foo<'r> {
+LL | struct Foo<'a> {
-LL |     x: &'r u32,
+LL |     x: &'a u32,
    |
 
 error[E0106]: missing lifetime specifier
@@ -18,8 +18,8 @@ LL |     Variant(&'_ u32),
    |
 help: consider introducing a named lifetime parameter
    |
-LL | enum Bar<'r> {
+LL | enum Bar<'a> {
-LL |     Variant(&'r u32),
+LL |     Variant(&'a u32),
    |
 
 error: aborting due to 2 previous errors

src/test/ui/underscore-lifetime/underscore-lifetime-binders.stderr

@@ -37,7 +37,7 @@ LL | fn foo2(_: &'_ u8, y: &'_ u8) -> &'_ u8 { y }
    |            ^^^^^^     ^^^^^^
 help: consider introducing a named lifetime parameter
    |
-LL | fn foo2<'r>(_: &'_ u8, y: &'_ u8) -> &'r u8 { y }
+LL | fn foo2<'a>(_: &'_ u8, y: &'_ u8) -> &'a u8 { y }
    |        ^^^^                           ^^
 
 error: aborting due to 5 previous errors