Skip to content

Commit b00e408

Browse files
fmeasefmease
committed
Generalize E0401
1 parent 3cd97ed commit b00e408

35 files changed

+141
-153
lines changed

‎compiler/rustc_error_codes/src/error_codes/E0401.md

+3-3
Original file line numberDiff line numberDiff line change
@@ -1,4 +1,4 @@
1-
Inner items do not inherit type or const parameters from the functions
1+
Inner items do not inherit the generic parameters from the items
22
they are embedded in.
33

44
Erroneous code example:
@@ -32,8 +32,8 @@ fn foo<T>(x: T) {
3232
}
3333
```
3434

35-
Items inside functions are basically just like top-level items, except
36-
that they can only be used from the function they are in.
35+
Items nested inside other items are basically just like top-level items, except
36+
that they can only be used from the item they are in.
3737

3838
There are a couple of solutions for this.
3939

‎compiler/rustc_resolve/src/diagnostics.rs

+8-14
Original file line numberDiff line numberDiff line change
@@ -553,14 +553,14 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
553553
resolution_error: ResolutionError<'a>,
554554
) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
555555
match resolution_error {
556-
ResolutionError::GenericParamsFromOuterFunction(outer_res, has_generic_params) => {
556+
ResolutionError::GenericParamsFromOuterItem(outer_res, has_generic_params) => {
557557
let mut err = struct_span_err!(
558558
self.tcx.sess,
559559
span,
560560
E0401,
561-
"can't use generic parameters from outer function",
561+
"can't use generic parameters from outer item",
562562
);
563-
err.span_label(span, "use of generic parameter from outer function");
563+
err.span_label(span, "use of generic parameter from outer item");
564564

565565
let sm = self.tcx.sess.source_map();
566566
let def_id = match outer_res {
@@ -573,33 +573,28 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
573573
reduce_impl_span_to_impl_keyword(sm, self.def_span(def_id)),
574574
"`Self` type implicitly declared here, by this `impl`",
575575
);
576-
err.span_label(span, "use a type here instead");
576+
err.span_label(span, "refer to the type directly here instead");
577577
return err;
578578
}
579579
Res::Def(DefKind::TyParam, def_id) => {
580-
err.span_label(self.def_span(def_id), "type parameter from outer function");
580+
err.span_label(self.def_span(def_id), "type parameter from outer item");
581581
def_id
582582
}
583583
Res::Def(DefKind::ConstParam, def_id) => {
584-
err.span_label(
585-
self.def_span(def_id),
586-
"const parameter from outer function",
587-
);
584+
err.span_label(self.def_span(def_id), "const parameter from outer item");
588585
def_id
589586
}
590587
_ => {
591588
bug!(
592-
"GenericParamsFromOuterFunction should only be used with \
589+
"GenericParamsFromOuterItem should only be used with \
593590
Res::SelfTyParam, Res::SelfTyAlias, DefKind::TyParam or \
594591
DefKind::ConstParam"
595592
);
596593
}
597594
};
598595

599596
if let HasGenericParams::Yes(span) = has_generic_params {
600-
// Try to retrieve the span of the function signature and generate a new
601-
// message with a local type or const parameter.
602-
let sugg_msg = "try using a local generic parameter instead";
597+
let sugg_msg = "try introducing a local generic parameter here";
603598
let name = self.tcx.item_name(def_id);
604599
let (span, snippet) = if span.is_empty() {
605600
let snippet = format!("<{name}>");
@@ -609,7 +604,6 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
609604
let snippet = format!("{name}, ");
610605
(span, snippet)
611606
};
612-
// Suggest the modification to the user
613607
err.span_suggestion(span, sugg_msg, snippet, Applicability::MaybeIncorrect);
614608
}
615609

‎compiler/rustc_resolve/src/ident.rs

+2-8
Original file line numberDiff line numberDiff line change
@@ -1229,10 +1229,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
12291229
if let Some(span) = finalize {
12301230
self.report_error(
12311231
span,
1232-
ResolutionError::GenericParamsFromOuterFunction(
1233-
res,
1234-
has_generic_params,
1235-
),
1232+
ResolutionError::GenericParamsFromOuterItem(res, has_generic_params),
12361233
);
12371234
}
12381235
return Res::Err;
@@ -1296,10 +1293,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
12961293
if let Some(span) = finalize {
12971294
self.report_error(
12981295
span,
1299-
ResolutionError::GenericParamsFromOuterFunction(
1300-
res,
1301-
has_generic_params,
1302-
),
1296+
ResolutionError::GenericParamsFromOuterItem(res, has_generic_params),
13031297
);
13041298
}
13051299
return Res::Err;

‎compiler/rustc_resolve/src/lib.rs

+2-2
Original file line numberDiff line numberDiff line change
@@ -186,8 +186,8 @@ struct BindingError {
186186

187187
#[derive(Debug)]
188188
enum ResolutionError<'a> {
189-
/// Error E0401: can't use type or const parameters from outer function.
190-
GenericParamsFromOuterFunction(Res, HasGenericParams),
189+
/// Error E0401: can't use type or const parameters from outer item.
190+
GenericParamsFromOuterItem(Res, HasGenericParams),
191191
/// Error E0403: the name is already used for a type or const parameter in this generic
192192
/// parameter list.
193193
NameAlreadyUsedInParameterList(Symbol, Span),

‎tests/ui/const-generics/early/const-param-from-outer-fn.rs

+1-1
Original file line numberDiff line numberDiff line change
@@ -1,6 +1,6 @@
11
fn foo<const X: u32>() {
22
fn bar() -> u32 {
3-
X //~ ERROR can't use generic parameters from outer function
3+
X //~ ERROR can't use generic parameters from outer item
44
}
55
}
66

‎tests/ui/const-generics/early/const-param-from-outer-fn.stderr

+4-4
Original file line numberDiff line numberDiff line change
@@ -1,12 +1,12 @@
1-
error[E0401]: can't use generic parameters from outer function
1+
error[E0401]: can't use generic parameters from outer item
22
--> $DIR/const-param-from-outer-fn.rs:3:9
33
|
44
LL | fn foo<const X: u32>() {
5-
| - const parameter from outer function
5+
| - const parameter from outer item
66
LL | fn bar() -> u32 {
7-
| - help: try using a local generic parameter instead: `<X>`
7+
| - help: try introducing a local generic parameter here: `<X>`
88
LL | X
9-
| ^ use of generic parameter from outer function
9+
| ^ use of generic parameter from outer item
1010

1111
error: aborting due to previous error
1212

‎tests/ui/error-codes/E0401.stderr

+11-11
Original file line numberDiff line numberDiff line change
@@ -1,26 +1,26 @@
1-
error[E0401]: can't use generic parameters from outer function
1+
error[E0401]: can't use generic parameters from outer item
22
--> $DIR/E0401.rs:4:39
33
|
44
LL | fn foo<T>(x: T) {
5-
| - type parameter from outer function
5+
| - type parameter from outer item
66
LL | fn bfnr<U, V: Baz<U>, W: Fn()>(y: T) {
7-
| - ^ use of generic parameter from outer function
7+
| - ^ use of generic parameter from outer item
88
| |
9-
| help: try using a local generic parameter instead: `T,`
9+
| help: try introducing a local generic parameter here: `T,`
1010

11-
error[E0401]: can't use generic parameters from outer function
11+
error[E0401]: can't use generic parameters from outer item
1212
--> $DIR/E0401.rs:9:16
1313
|
1414
LL | fn foo<T>(x: T) {
15-
| - type parameter from outer function
15+
| - type parameter from outer item
1616
...
1717
LL | fn baz<U,
18-
| - help: try using a local generic parameter instead: `T,`
18+
| - help: try introducing a local generic parameter here: `T,`
1919
...
2020
LL | (y: T) {
21-
| ^ use of generic parameter from outer function
21+
| ^ use of generic parameter from outer item
2222

23-
error[E0401]: can't use generic parameters from outer function
23+
error[E0401]: can't use generic parameters from outer item
2424
--> $DIR/E0401.rs:24:25
2525
|
2626
LL | impl<T> Iterator for A<T> {
@@ -29,8 +29,8 @@ LL | impl<T> Iterator for A<T> {
2929
LL | fn helper(sel: &Self) -> u8 {
3030
| ^^^^
3131
| |
32-
| use of generic parameter from outer function
33-
| use a type here instead
32+
| use of generic parameter from outer item
33+
| refer to the type directly here instead
3434

3535
error[E0282]: type annotations needed
3636
--> $DIR/E0401.rs:11:5

‎tests/ui/generics/issue-94432-garbage-ice.rs

+1-1
Original file line numberDiff line numberDiff line change
@@ -4,7 +4,7 @@
44

55
fn�a<e>(){fn�p(){e}} //~ ERROR unknown start of token: \u{fffd}
66
//~^ ERROR unknown start of token: \u{fffd}
7-
//~^^ ERROR can't use generic parameters from outer function [E0401]
7+
//~^^ ERROR can't use generic parameters from outer item [E0401]
88
//~^^^ WARN type parameter `e` should have an upper camel case name
99

1010
fn main(){}

‎tests/ui/generics/issue-98432.rs

+1-1
Original file line numberDiff line numberDiff line change
@@ -2,7 +2,7 @@ struct Struct<T>(T);
22

33
impl<T> Struct<T> {
44
const CONST: fn() = || {
5-
struct _Obligation where T:; //~ ERROR can't use generic parameters from outer function
5+
struct _Obligation where T:; //~ ERROR can't use generic parameters from outer item
66
};
77
}
88

‎tests/ui/generics/issue-98432.stderr

+4-4
Original file line numberDiff line numberDiff line change
@@ -1,13 +1,13 @@
1-
error[E0401]: can't use generic parameters from outer function
1+
error[E0401]: can't use generic parameters from outer item
22
--> $DIR/issue-98432.rs:5:34
33
|
44
LL | impl<T> Struct<T> {
5-
| - type parameter from outer function
5+
| - type parameter from outer item
66
LL | const CONST: fn() = || {
77
LL | struct _Obligation where T:;
8-
| - ^ use of generic parameter from outer function
8+
| - ^ use of generic parameter from outer item
99
| |
10-
| help: try using a local generic parameter instead: `<T>`
10+
| help: try introducing a local generic parameter here: `<T>`
1111

1212
error: aborting due to previous error
1313

‎tests/ui/inner-static-type-parameter.rs

+1-1
Original file line numberDiff line numberDiff line change
@@ -4,7 +4,7 @@ enum Bar<T> { What } //~ ERROR parameter `T` is never used
44

55
fn foo<T>() {
66
static a: Bar<T> = Bar::What;
7-
//~^ ERROR can't use generic parameters from outer function
7+
//~^ ERROR can't use generic parameters from outer item
88
}
99

1010
fn main() {

‎tests/ui/inner-static-type-parameter.stderr

+3-3
Original file line numberDiff line numberDiff line change
@@ -1,10 +1,10 @@
1-
error[E0401]: can't use generic parameters from outer function
1+
error[E0401]: can't use generic parameters from outer item
22
--> $DIR/inner-static-type-parameter.rs:6:19
33
|
44
LL | fn foo<T>() {
5-
| - type parameter from outer function
5+
| - type parameter from outer item
66
LL | static a: Bar<T> = Bar::What;
7-
| ^ use of generic parameter from outer function
7+
| ^ use of generic parameter from outer item
88

99
error[E0392]: parameter `T` is never used
1010
--> $DIR/inner-static-type-parameter.rs:3:10

‎tests/ui/issues/issue-3214.rs

+1-1
Original file line numberDiff line numberDiff line change
@@ -1,6 +1,6 @@
11
fn foo<T>() {
22
struct Foo {
3-
x: T, //~ ERROR can't use generic parameters from outer function
3+
x: T, //~ ERROR can't use generic parameters from outer item
44
}
55

66
impl<T> Drop for Foo<T> {

‎tests/ui/issues/issue-3214.stderr

+4-4
Original file line numberDiff line numberDiff line change
@@ -1,12 +1,12 @@
1-
error[E0401]: can't use generic parameters from outer function
1+
error[E0401]: can't use generic parameters from outer item
22
--> $DIR/issue-3214.rs:3:12
33
|
44
LL | fn foo<T>() {
5-
| - type parameter from outer function
5+
| - type parameter from outer item
66
LL | struct Foo {
7-
| - help: try using a local generic parameter instead: `<T>`
7+
| - help: try introducing a local generic parameter here: `<T>`
88
LL | x: T,
9-
| ^ use of generic parameter from outer function
9+
| ^ use of generic parameter from outer item
1010

1111
error[E0107]: struct takes 0 generic arguments but 1 generic argument was supplied
1212
--> $DIR/issue-3214.rs:6:22

‎tests/ui/issues/issue-5997-enum.rs

+1-1
Original file line numberDiff line numberDiff line change
@@ -1,6 +1,6 @@
11
fn f<Z>() -> bool {
22
enum E { V(Z) }
3-
//~^ ERROR can't use generic parameters from outer function
3+
//~^ ERROR can't use generic parameters from outer item
44
true
55
}
66

‎tests/ui/issues/issue-5997-enum.stderr

+4-4
Original file line numberDiff line numberDiff line change
@@ -1,12 +1,12 @@
1-
error[E0401]: can't use generic parameters from outer function
1+
error[E0401]: can't use generic parameters from outer item
22
--> $DIR/issue-5997-enum.rs:2:16
33
|
44
LL | fn f<Z>() -> bool {
5-
| - type parameter from outer function
5+
| - type parameter from outer item
66
LL | enum E { V(Z) }
7-
| - ^ use of generic parameter from outer function
7+
| - ^ use of generic parameter from outer item
88
| |
9-
| help: try using a local generic parameter instead: `<Z>`
9+
| help: try introducing a local generic parameter here: `<Z>`
1010

1111
error: aborting due to previous error
1212

‎tests/ui/issues/issue-5997-struct.rs

+1-1
Original file line numberDiff line numberDiff line change
@@ -1,5 +1,5 @@
11
fn f<T>() -> bool {
2-
struct S(T); //~ ERROR can't use generic parameters from outer function
2+
struct S(T); //~ ERROR can't use generic parameters from outer item
33

44
true
55
}

‎tests/ui/issues/issue-5997-struct.stderr

+4-4
Original file line numberDiff line numberDiff line change
@@ -1,12 +1,12 @@
1-
error[E0401]: can't use generic parameters from outer function
1+
error[E0401]: can't use generic parameters from outer item
22
--> $DIR/issue-5997-struct.rs:2:14
33
|
44
LL | fn f<T>() -> bool {
5-
| - type parameter from outer function
5+
| - type parameter from outer item
66
LL | struct S(T);
7-
| -^ use of generic parameter from outer function
7+
| -^ use of generic parameter from outer item
88
| |
9-
| help: try using a local generic parameter instead: `<T>`
9+
| help: try introducing a local generic parameter here: `<T>`
1010

1111
error: aborting due to previous error
1212

‎tests/ui/nested-ty-params.rs

+1-1
Original file line numberDiff line numberDiff line change
@@ -1,4 +1,4 @@
1-
// error-pattern:can't use generic parameters from outer function
1+
// error-pattern:can't use generic parameters from outer item
22
fn hd<U>(v: Vec<U> ) -> U {
33
fn hd1(w: [U]) -> U { return w[0]; }
44

‎tests/ui/nested-ty-params.stderr

+8-8
Original file line numberDiff line numberDiff line change
@@ -1,22 +1,22 @@
1-
error[E0401]: can't use generic parameters from outer function
1+
error[E0401]: can't use generic parameters from outer item
22
--> $DIR/nested-ty-params.rs:3:16
33
|
44
LL | fn hd<U>(v: Vec<U> ) -> U {
5-
| - type parameter from outer function
5+
| - type parameter from outer item
66
LL | fn hd1(w: [U]) -> U { return w[0]; }
7-
| - ^ use of generic parameter from outer function
7+
| - ^ use of generic parameter from outer item
88
| |
9-
| help: try using a local generic parameter instead: `<U>`
9+
| help: try introducing a local generic parameter here: `<U>`
1010

11-
error[E0401]: can't use generic parameters from outer function
11+
error[E0401]: can't use generic parameters from outer item
1212
--> $DIR/nested-ty-params.rs:3:23
1313
|
1414
LL | fn hd<U>(v: Vec<U> ) -> U {
15-
| - type parameter from outer function
15+
| - type parameter from outer item
1616
LL | fn hd1(w: [U]) -> U { return w[0]; }
17-
| - ^ use of generic parameter from outer function
17+
| - ^ use of generic parameter from outer item
1818
| |
19-
| help: try using a local generic parameter instead: `<U>`
19+
| help: try introducing a local generic parameter here: `<U>`
2020

2121
error: aborting due to 2 previous errors
2222

‎tests/ui/resolve/bad-type-env-capture.stderr

+4-4
Original file line numberDiff line numberDiff line change
@@ -1,12 +1,12 @@
1-
error[E0401]: can't use generic parameters from outer function
1+
error[E0401]: can't use generic parameters from outer item
22
--> $DIR/bad-type-env-capture.rs:2:15
33
|
44
LL | fn foo<T>() {
5-
| - type parameter from outer function
5+
| - type parameter from outer item
66
LL | fn bar(b: T) { }
7-
| - ^ use of generic parameter from outer function
7+
| - ^ use of generic parameter from outer item
88
| |
9-
| help: try using a local generic parameter instead: `<T>`
9+
| help: try introducing a local generic parameter here: `<T>`
1010

1111
error: aborting due to previous error
1212

‎tests/ui/resolve/issue-12796.rs

+1-1
Original file line numberDiff line numberDiff line change
@@ -1,7 +1,7 @@
11
trait Trait {
22
fn outer(&self) {
33
fn inner(_: &Self) {
4-
//~^ ERROR can't use generic parameters from outer function
4+
//~^ ERROR can't use generic parameters from outer item
55
}
66
}
77
}

‎tests/ui/resolve/issue-12796.stderr

+2-2
Original file line numberDiff line numberDiff line change
@@ -1,10 +1,10 @@
1-
error[E0401]: can't use generic parameters from outer function
1+
error[E0401]: can't use generic parameters from outer item
22
--> $DIR/issue-12796.rs:3:22
33
|
44
LL | fn inner(_: &Self) {
55
| ^^^^
66
| |
7-
| use of generic parameter from outer function
7+
| use of generic parameter from outer item
88
| can't use `Self` here
99

1010
error: aborting due to previous error

0 commit comments

Comments
 (0)