src/test/ui/impl-trait/where-allowed.stderr

   1 error[E0666]: nested `impl Trait` is not allowed
   2   --> $DIR/where-allowed.rs:47:51
   3    |
   4 LL | fn in_impl_Fn_parameter_in_parameters(_: &impl Fn(impl Debug)) { panic!() }
   5    |                                           --------^^^^^^^^^^-
   6    |                                           |       |
   7    |                                           |       nested `impl Trait` here
   8    |                                           outer `impl Trait`
   9
  10 error[E0666]: nested `impl Trait` is not allowed
  11   --> $DIR/where-allowed.rs:56:57
  12    |
  13 LL | fn in_impl_Fn_parameter_in_return() -> &'static impl Fn(impl Debug) { panic!() }
  14    |                                                 --------^^^^^^^^^^-
  15    |                                                 |       |
  16    |                                                 |       nested `impl Trait` here
  17    |                                                 outer `impl Trait`
  18
  19 error[E0658]: `impl Trait` in type aliases is unstable
  20   --> $DIR/where-allowed.rs:118:16
  21    |
  22 LL |     type Out = impl Debug;
  23    |                ^^^^^^^^^^
  24    |
  25    = note: see issue #63063 <https://github.com/rust-lang/rust/issues/63063> for more information
  26    = help: add `#![feature(type_alias_impl_trait)]` to the crate attributes to enable
  27
  28 error[E0658]: `impl Trait` in type aliases is unstable
  29   --> $DIR/where-allowed.rs:153:23
  30    |
  31 LL | type InTypeAlias<R> = impl Debug;
  32    |                       ^^^^^^^^^^
  33    |
  34    = note: see issue #63063 <https://github.com/rust-lang/rust/issues/63063> for more information
  35    = help: add `#![feature(type_alias_impl_trait)]` to the crate attributes to enable
  36
  37 error[E0658]: `impl Trait` in type aliases is unstable
  38   --> $DIR/where-allowed.rs:156:39
  39    |
  40 LL | type InReturnInTypeAlias<R> = fn() -> impl Debug;
  41    |                                       ^^^^^^^^^^
  42    |
  43    = note: see issue #63063 <https://github.com/rust-lang/rust/issues/63063> for more information
  44    = help: add `#![feature(type_alias_impl_trait)]` to the crate attributes to enable
  45
  46 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `fn` pointer param
  47   --> $DIR/where-allowed.rs:16:40
  48    |
  49 LL | fn in_fn_parameter_in_parameters(_: fn(impl Debug)) { panic!() }
  50    |                                        ^^^^^^^^^^
  51
  52 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `fn` pointer return
  53   --> $DIR/where-allowed.rs:20:42
  54    |
  55 LL | fn in_fn_return_in_parameters(_: fn() -> impl Debug) { panic!() }
  56    |                                          ^^^^^^^^^^
  57
  58 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `fn` pointer param
  59   --> $DIR/where-allowed.rs:24:38
  60    |
  61 LL | fn in_fn_parameter_in_return() -> fn(impl Debug) { panic!() }
  62    |                                      ^^^^^^^^^^
  63
  64 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `fn` pointer return
  65   --> $DIR/where-allowed.rs:28:40
  66    |
  67 LL | fn in_fn_return_in_return() -> fn() -> impl Debug { panic!() }
  68    |                                        ^^^^^^^^^^
  69
  70 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait param
  71   --> $DIR/where-allowed.rs:32:49
  72    |
  73 LL | fn in_dyn_Fn_parameter_in_parameters(_: &dyn Fn(impl Debug)) { panic!() }
  74    |                                                 ^^^^^^^^^^
  75
  76 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
  77   --> $DIR/where-allowed.rs:36:51
  78    |
  79 LL | fn in_dyn_Fn_return_in_parameters(_: &dyn Fn() -> impl Debug) { panic!() }
  80    |                                                   ^^^^^^^^^^
  81
  82 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait param
  83   --> $DIR/where-allowed.rs:40:55
  84    |
  85 LL | fn in_dyn_Fn_parameter_in_return() -> &'static dyn Fn(impl Debug) { panic!() }
  86    |                                                       ^^^^^^^^^^
  87
  88 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait param
  89   --> $DIR/where-allowed.rs:47:51
  90    |
  91 LL | fn in_impl_Fn_parameter_in_parameters(_: &impl Fn(impl Debug)) { panic!() }
  92    |                                                   ^^^^^^^^^^
  93
  94 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
  95   --> $DIR/where-allowed.rs:52:53
  96    |
  97 LL | fn in_impl_Fn_return_in_parameters(_: &impl Fn() -> impl Debug) { panic!() }
  98    |                                                     ^^^^^^^^^^
  99
 100 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait param
 101   --> $DIR/where-allowed.rs:56:57
 102    |
 103 LL | fn in_impl_Fn_parameter_in_return() -> &'static impl Fn(impl Debug) { panic!() }
 104    |                                                         ^^^^^^^^^^
 105
 106 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait param
 107   --> $DIR/where-allowed.rs:64:38
 108    |
 109 LL | fn in_Fn_parameter_in_generics<F: Fn(impl Debug)> (_: F) { panic!() }
 110    |                                      ^^^^^^^^^^
 111
 112 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
 113   --> $DIR/where-allowed.rs:68:40
 114    |
 115 LL | fn in_Fn_return_in_generics<F: Fn() -> impl Debug> (_: F) { panic!() }
 116    |                                        ^^^^^^^^^^
 117
 118 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 119   --> $DIR/where-allowed.rs:81:32
 120    |
 121 LL | struct InBraceStructField { x: impl Debug }
 122    |                                ^^^^^^^^^^
 123
 124 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in path
 125   --> $DIR/where-allowed.rs:85:41
 126    |
 127 LL | struct InAdtInBraceStructField { x: Vec<impl Debug> }
 128    |                                         ^^^^^^^^^^
 129
 130 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 131   --> $DIR/where-allowed.rs:89:27
 132    |
 133 LL | struct InTupleStructField(impl Debug);
 134    |                           ^^^^^^^^^^
 135
 136 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 137   --> $DIR/where-allowed.rs:94:25
 138    |
 139 LL |     InBraceVariant { x: impl Debug },
 140    |                         ^^^^^^^^^^
 141
 142 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 143   --> $DIR/where-allowed.rs:96:20
 144    |
 145 LL |     InTupleVariant(impl Debug),
 146    |                    ^^^^^^^^^^
 147
 148 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in trait method return
 149   --> $DIR/where-allowed.rs:107:23
 150    |
 151 LL |     fn in_return() -> impl Debug;
 152    |                       ^^^^^^^^^^
 153    |
 154    = note: see issue #91611 <https://github.com/rust-lang/rust/issues/91611> for more information
 155    = help: add `#![feature(return_position_impl_trait_in_trait)]` to the crate attributes to enable
 156
 157 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `impl` method return
 158   --> $DIR/where-allowed.rs:124:34
 159    |
 160 LL |     fn in_trait_impl_return() -> impl Debug { () }
 161    |                                  ^^^^^^^^^^
 162    |
 163    = note: see issue #91611 <https://github.com/rust-lang/rust/issues/91611> for more information
 164    = help: add `#![feature(return_position_impl_trait_in_trait)]` to the crate attributes to enable
 165
 166 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `extern fn` param
 167   --> $DIR/where-allowed.rs:137:33
 168    |
 169 LL |     fn in_foreign_parameters(_: impl Debug);
 170    |                                 ^^^^^^^^^^
 171
 172 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `extern fn` return
 173   --> $DIR/where-allowed.rs:140:31
 174    |
 175 LL |     fn in_foreign_return() -> impl Debug;
 176    |                               ^^^^^^^^^^
 177
 178 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `fn` pointer return
 179   --> $DIR/where-allowed.rs:156:39
 180    |
 181 LL | type InReturnInTypeAlias<R> = fn() -> impl Debug;
 182    |                                       ^^^^^^^^^^
 183
 184 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in trait
 185   --> $DIR/where-allowed.rs:161:16
 186    |
 187 LL | impl PartialEq<impl Debug> for () {
 188    |                ^^^^^^^^^^
 189
 190 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 191   --> $DIR/where-allowed.rs:166:24
 192    |
 193 LL | impl PartialEq<()> for impl Debug {
 194    |                        ^^^^^^^^^^
 195
 196 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 197   --> $DIR/where-allowed.rs:171:6
 198    |
 199 LL | impl impl Debug {
 200    |      ^^^^^^^^^^
 201
 202 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 203   --> $DIR/where-allowed.rs:177:24
 204    |
 205 LL | impl InInherentImplAdt<impl Debug> {
 206    |                        ^^^^^^^^^^
 207
 208 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 209   --> $DIR/where-allowed.rs:183:11
 210    |
 211 LL |     where impl Debug: Debug
 212    |           ^^^^^^^^^^
 213
 214 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 215   --> $DIR/where-allowed.rs:190:15
 216    |
 217 LL |     where Vec<impl Debug>: Debug
 218    |               ^^^^^^^^^^
 219
 220 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in bound
 221   --> $DIR/where-allowed.rs:197:24
 222    |
 223 LL |     where T: PartialEq<impl Debug>
 224    |                        ^^^^^^^^^^
 225
 226 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait param
 227   --> $DIR/where-allowed.rs:204:17
 228    |
 229 LL |     where T: Fn(impl Debug)
 230    |                 ^^^^^^^^^^
 231
 232 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
 233   --> $DIR/where-allowed.rs:211:22
 234    |
 235 LL |     where T: Fn() -> impl Debug
 236    |                      ^^^^^^^^^^
 237
 238 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 239   --> $DIR/where-allowed.rs:217:40
 240    |
 241 LL | struct InStructGenericParamDefault<T = impl Debug>(T);
 242    |                                        ^^^^^^^^^^
 243
 244 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 245   --> $DIR/where-allowed.rs:221:36
 246    |
 247 LL | enum InEnumGenericParamDefault<T = impl Debug> { Variant(T) }
 248    |                                    ^^^^^^^^^^
 249
 250 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 251   --> $DIR/where-allowed.rs:225:38
 252    |
 253 LL | trait InTraitGenericParamDefault<T = impl Debug> {}
 254    |                                      ^^^^^^^^^^
 255
 256 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 257   --> $DIR/where-allowed.rs:229:41
 258    |
 259 LL | type InTypeAliasGenericParamDefault<T = impl Debug> = T;
 260    |                                         ^^^^^^^^^^
 261
 262 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 263   --> $DIR/where-allowed.rs:233:11
 264    |
 265 LL | impl <T = impl Debug> T {}
 266    |           ^^^^^^^^^^
 267
 268 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
 269   --> $DIR/where-allowed.rs:240:40
 270    |
 271 LL | fn in_method_generic_param_default<T = impl Debug>(_: T) {}
 272    |                                        ^^^^^^^^^^
 273
 274 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in variable binding
 275   --> $DIR/where-allowed.rs:246:29
 276    |
 277 LL |     let _in_local_variable: impl Fn() = || {};
 278    |                             ^^^^^^^^^
 279
 280 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in closure return
 281   --> $DIR/where-allowed.rs:248:46
 282    |
 283 LL |     let _in_return_in_local_variable = || -> impl Fn() { || {} };
 284    |                                              ^^^^^^^^^
 285
 286 error: defaults for type parameters are only allowed in `struct`, `enum`, `type`, or `trait` definitions
 287   --> $DIR/where-allowed.rs:233:7
 288    |
 289 LL | impl <T = impl Debug> T {}
 290    |       ^^^^^^^^^^^^^^
 291    |
 292    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
 293    = note: for more information, see issue #36887 <https://github.com/rust-lang/rust/issues/36887>
 294    = note: `#[deny(invalid_type_param_default)]` on by default
 295
 296 error: defaults for type parameters are only allowed in `struct`, `enum`, `type`, or `trait` definitions
 297   --> $DIR/where-allowed.rs:240:36
 298    |
 299 LL | fn in_method_generic_param_default<T = impl Debug>(_: T) {}
 300    |                                    ^^^^^^^^^^^^^^
 301    |
 302    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
 303    = note: for more information, see issue #36887 <https://github.com/rust-lang/rust/issues/36887>
 304
 305 error[E0118]: no nominal type found for inherent implementation
 306   --> $DIR/where-allowed.rs:233:23
 307    |
 308 LL | impl <T = impl Debug> T {}
 309    |                       ^ impl requires a nominal type
 310    |
 311    = note: either implement a trait on it or create a newtype to wrap it instead
 312
 313 error: aborting due to 47 previous errors
 314
 315 Some errors have detailed explanations: E0118, E0562, E0658, E0666.
 316 For more information about an error, try `rustc --explain E0118`.